MSX Technical Data Book
Hardware/Software Specifications
Presented by
Robey's MSX Workshop
Originaly scanned by
Ivan Latorre
Converted to PDF
Eduardo Robsy
[September 2004]
MSX Technical Data Book
Hardware/Software Specifications
SONY
Sony Corporation
4 14 1, Asahi-cho, Atsugi-shi,
Kanagawa-ken, 243 Japan
Copyright © 1984 Microsoft Corporation
Produced by ASCII Corporation
Printed in Japan
PREFACE
The Microsoft MSX standard was invented to provide end users
and software developers with a standardized computer so that
programs could run on any computer even though they were made by
different manufacturers.
This book presents the MSX specifications in detail. It is
intended to be a reference for advanced programmers and software
developers. The information is generally divided four parts.
Part A, MSX HARDWARE SPECIFICATIONS, presents the specifications
for the MSX system hardware.
Chapter 1, Hardware Specification, covers the MSX standard
hardware configuration in terms of the requirements for the LSIs,
memory size, interrupts, screen, keyboard, and sound used in the
main unit; and the various (cassette, floppy, printer, serial, and
slot) interfaces and connectors. It also covers topics such as
cartridges, expansion, ports, and memory maps.
Part B, MSX SYSTEM SOFTWARE, contains a reference guide for MSX-
BASIC and information for advanced programming.
Chapter 2, Language Specification, is a guide to MSX-BASIC
and is for use with advanced programming requiring machine lan¬
guage routines.
Part C, EXPANDED MSX SYSTEM SOFTWARE, is about the advanced fea¬
tures of MSX, including Expanded Disk BASIC and MSX-DOS.
Chapter 3, MSX-DOS, contains a user's guide to MSX-DOS and
Disk BASIC, and includes information needed for the advanced
programmer.
Chapter 4, Other Expansion, covers the serial (RS-232C) ex¬
pansion and BIOS calls available in the extended version.
Part D, SOFTWARE DEVELOPMENT GUIDE, contains information for soft¬
ware developers.
Chapter 5, International MSX Versions and their Differences,
is for manufacturers or programmers who wish to make the hardware
or software be usable internationally.
Chapter 6, Notes for MSX Software Developers, contains
information that software developers should consider when
programming for MSX computers.
1
Syntax Notation in Reference Sections
Wherever the format for a statement/command or a function is given,
the following rules apply:
CAPS Items in capital letters must be input as shown.
< > Items in lowercase letters enclosed in angle brackets (< >)
are to be supplied by the user.
[ ] Items in square brackets {[ ]) are optional.
... Items followed by an ellipsis (...) may be repeated any
number of times (up to the length of the line).
{ } Braces indicate that the user has a choice between two or
more entries. At least one of the entries enclosed in
braces must be chosen unless the entries are also enclosed
in square brackets.
I Vertical bars separate the choices within braces. At least
one of the entries separated by bars must be chosen unless
the entries are also enclosed in square brackets.
All punctuation except angle brackets and square
brackets (i.e., commas, parentheses, semicolons,
hyphens, equal signs) must be included where shown.
Arguments to functions are always enclosed in parentheses. In the
formats given for the functions in this book, the arguments are
abbreviated as follows:
X and Y
I and J
X$ and Y$
Represent any numeric expressions.
Represent integer expressions.
Represent string expressions.
2
CONTENTS
PART A MSX HARDWARE SPECIFICATIONS
1. Hardware Specifications
1.1 MSX Standard..
1.2 MSX System Configuration.9
1.3 Main Unit.10
1.3.1 LSIs..
1.3.2 Memory .. 10
1.3.3 Interrupts.11
1.3.4 Screen. 12
1.3.5 Keyboard .. 13
1.3.6 Sound. .14
1.4 Interfaces. 15
1.4.1 Cassette Interface... 15
1.4.2 Floppy Disk Interface .18
1.4.3 Printer Interface .19
1.4.4 RS-232C Interface. 20
1.4.5 Peripheral I/O Port(s) .25
1.4.6 Joysticks . 27
1.4.7 Paddles. 28
1.4.8 Connectors .29
1.4.9 Slots. 30
1.5 Cartridges. 31
1.5.1 Cartridge Standard.31
1.5.2 Cartridge Bus .32
1.5.3 Cartridge Bus Connenction Conditions.34
1.5.4 Cartridge Power Capacity . .....34
1.5.5 Sample Circuit Diagram of Expanded Slot Select Signal35
1.6 Notes for System Expansion.36
1.6.1 RAM Expansion. ...36
1.6.2 Slot Expansion...36
1.6.3 I/O Expansion. 37
1.7 Address Maps ..3 8
1.7.1 Memory Map.3 8
1.7.2 I/O Address Map.40
1.7.3 Printer Port. 41
1.7.4 VDP Port. 41
1.7.5 PSG Port..
1.7.6 PPI Port. 41
1.7.7 External Memory {SONY) . 41
1.7.8 Light Pen (SANYO) .41
1.7.9 Audio/Video Control .42
1.7.10 Notes on I/O Address Assignments.42
1.7.11 82 55 (PPI) Bit Assignments .. 43
1.7.12 PSG Bit Assignments.44
PART B MSX SYSTEM SOFTWARE
2. Language Specifications
2.1 MSX BASIC Reference Guide .46
2.1.1 Modes of Operation. 46
3
2.1.2 Line Format... 47
2.1.3 Character Set . 47
2.1.4 Constants..
2.1.5 Variables..
2.1.6 Type Conversion.51
2.1.7 Expressions and Operators .53
2.1.8 Program Editing . 57
2.1.9 Special Keys.62
2.1.10 Error Messages.63
2.1.11 Commands and Statements except those doing I/O.63
2.1.12 Functions except those doing I/O.7 9
2.1.13 Device Specific Statements......84
2.1.14 I/O Functions. 100
2.1.15 Special Variables . 102
2.1.16 Machine Dependent Statements and Functions .104
2.1.17 Summary of Error Codes and Messages .105
2.1.18 MSX BASIC Reserved words .109
2.2 Advanced Programming Guide ...110
2.2.1 BIOS Entry List . 110
2.2.2 Work Area . 135
2.2.3 Slot Control . 161
2.2.4 Cassette I/O Mechanism .172
2.2.5 MSX Printer Specifications .177
PART C EXPANDED MSX SYSTEM SOFTWARE
3. MSX-DOS
3.1 MSX-DOS User's Guide .182
3.1.1 System Requirements .182
3.1.2 Getting Started. 182
3.1.3 Wild Cards .184
3.1.4 Illegal File Names .185
3.1.5 Directories...186
3.1.6 Types of MSX-DOS Commands . 186
3.1.7 Command Options .187
3.1.8 Information Common to All MSX-DOS Commands .188
3.1.9 Batch Processing .189
3.1.10 The AUTOEXEC.BAT File...190
3.1.11 How to Create a Batch File.191
3.1.12 Replaceable Parameters in .BAT File.192
3.1.13 MSX-DOS Editing and Function Keys.194
3.1.14 Instructions for Users with Single-drive Systems ...200
3.1.15 Disk Errors .201
3.2 MSX-DOS Command Guide . 202
3.3 MSX Disk BASIC Reference Guide .219
3.3.1 Commands and Statements.219
3.3.2 Functions.246
3.3.3 Error Codes and Error Messages .252
3.4 MSX-DOS and Disk BASIC Boot Procedure.255
3.5 MSX-DOS and Disk BASIC Disk Drivers.256
3.6 MSX-DOS System Calls. ....267
4
4. Other Expansion
4.1 MSX-RS23 2C Support.290
4.1.1 Extended BASIC for RS-232C Communication.291
4.1.2 Extended BIOS Calls Handling RS-232C.300
4.2 Other MSX Extended BIOS Calls.309
4.2.1 Extended BIOS Calls.309
4.2.2 Extended BIOS Maker ID Number .313
4.3 Tenkey Support on MSX.314
PART D SOFTWARE DEVELOPMENT GUIDE
5. International MSX Versions and their Differences
5.1 Introduction. 316
5.2 Keyboard.316
5.2.1 Keyboard Hardware. 316
5.2.2 Character Set.....317
5.2.3 Keyboard Layout .319
5.2.4 CAPS Lock .319
5.2.5 DEAD-Key Functions. 331
5.3 Screen Mode .333
5.4 Other Differences among Versions . 334
5.5 ID Bytes.335
6. Notes for MSX Software Developers.336
5
6
PART A
MSX HARDWARE SPECIFICATIONS
MSX HARDWARE SPECIFICATIONS
1* Hardware Specifications
1.1 MSX Standard
o CPU
Z80A compatible
o MEMORY
ROM: 32K bytes (MSX system software)
RAM: 16K bytes (Minimum)
o SCREEN DISPLAY
Text display: 32 x 24 (See Section 2.4)
Graphics: 256 x 192
Colors: 16
o CASSETTE TAPE
FSK format, 1200/2400 Baud
o SOUND
8 Octaves, 3 Voices
o KEYBOARD VERSIONS
Alphanumerics, Japanese, Graphics (Japanese)
Alphanumerics, European, Graphics (International)
O FLOPPY DISK DRIVES
Hardware depends on the manufacturer
Disk format MS-DOS-compatible
o PRINTER *
8 bit parallel
O ROM CARTRIDGE AND I/O BUS
Software cartridge and expansion BUS slots
o JOYSTICKS *
1 or 2
o CHINESE CHARACTERS *
At manufacturer's disgression
The items with asterisks may not be provided in the basic
system configuration.
8
MSX HARDWARE SPECIFICATIONS
1.2 MSX System Configuration
o MINIMUM CONFIGURATION
SOUND OUTPUT
VIDEO OUTPUT
ROM 32K
RAM 16K
PPI
KEYBOARD
CARTRIDGE SLOT x 1
CASSETTE
JOYSTICK
x 1
o SOFTWARE SUPPORT LIMIT
SOUND OUTPUT
VIDEO PRINTER
OUTPUT OUTPUT
CARTRIDGE
SLOTS x 15
Z80 A
ROM
32K
PSG
PPI
VDP
RAM 32K
for
BASIC
64K
for
DOS
KEYBOARD
CASSETTE
JOYSTICK
x 2
MSX HARDWARE SPECIFICATIONS
1.3 Main Unit
1.3.1 LSIs
o CPU
Z80A compatible
Clock 3.579545MHz (NTSC Color sub-carrier frequency)
1 WAIT in Ml CYCLE
O VDP
TI TMS-9918A compatible
o PSG
GI AY-3-8910 compatible
o PPI
Intel i-8255 compatible
1.3.2
Memory
O ROM
MSX-BASIC,
3 2K bytes
o RAM
Minimum 16K
bytes
NOTE
Since the minimum system
configuration contains four
slots, the memory area may be
expanded up to 256K bytes.
Each slot can be further
expanded to have four slots,
for a total of 16 slots. Thus
the maximum memory space is 1
megabyte.
The BASIC ROM interpreter
occupies addresses 0000 to
7FFF, and the RAM addresses
start at FFFF and grows down¬
ward on the memory map.
See the memory map in Section
1.7 for details.
10
MSX HARDWARE SPECIFICATIONS
1.3.3 Interrupts
o NMI
Not used. MSX ROM only provides a RAM hook.
o INT
Interrupts are accepted from the VDP and the cartridges.
The interrupt mode is 1. (Branch to 38H) The MSX system
software uses an interrupt from the VDP. The interrupt
intervals are 60 Hz in the NTSC version and 50 Hz in the
PAL/SECAM version.
It is not possible to support
NMI under MSX-DOS because the
address 66H (an entry vector
for the NMI) is used by the
MSX-DOS FCB data.
11
MSX HARDWARE SPECIFICATIONS
1.3.4 Screen
o LSI
TI TMS9918A Compatible
o Character set
Alphanumerics + Japanese (European) + Graphics
256 patterns, 8x8 dots
o Col or
16 colors
o Sprites
32 sprites, with a maximum of four sprites on the same
horizontal line.
o Display modes
MODE
RES.
SIZE
NO. I
* I COLOR
SPRITE
AVAIL.
NO. OF I
CHARS. I
I LSI
Graphic I Spec.
|-—-
I fSuggested
I value
256
xl92
-H
240
x!92
8x8
I 16
256 I colors
I
Yes
I
32x241
--i
I
29X241
I LSI
Graphic I Spec.
256
xl92
II iSuggested
I value
4 8x8
240
xl92
I 16
7681 colors
I
Yes
32x24!
29X241
I LSI
Multi-I Spec.
color t--
ISuggested
I value
64
x48blk
--I
64
x40blk
4x4
/Block
! 16
- I colors
I
Yes
I
32x241
29x24!
+-
I LSI
I Spec.
Text v -
I Suggested
I value
256
xl92
240
xl93
8x6
I
I 2
256 I out of
I 16
I colors
No
I
40x24
39x241
______ J
* Number of patterns
Suggested
val ues
The eight pixels from the left and right of the
horizontal line are not used by the software.
12
MSX HARDWARE SPECIFICATIONS
1.3.5 Keyboard
o Layout
Alphanumerics : ASCII standard
Japanese syllables : JIS standard syllable layout
European : International versions
Graphic Characters : Depending on international version
(Selected by jumper connection)
o Scanning
Software scanning driven by VDP interrupt
o Number of keys
72
See section 5.2.2/5.2.3 for details,
o Matrix diagram
★ Underscore character.
*★ Code Lock key in international versions.
13
MSX HARDWARE SPECIFICATIONS
1.3.6 Sound
0 LSI
GI AY-3-8910 Compatible. Clock 1.7 8977 25 MHz (1/2 CPU clock)
o OCTAVES
8 Octaves (3 Voices)
O SOUND EFFECTS
Available
O SOFTWARE SOUND OUTPUT
1 bit from output port
o OUTPUT LEVEL
-5dbm (Providing the system has an output connector)
o CONNECTOR
RCA 2 pins (Providing the system has an output connector)
14
MSX HARDWARE SPECIFICATIONS
1.4 Interfaces
1.4.1 Cassette Interface
o INPUT
From the earphone
terminal
of
the
tape
recorder
o OUTPUT
To the microphone
terminal
of
the
tape
recorder
o SYNCHRONIZATION
Asynchronous, software-controlled
o BAUD RATES
1200 baud (1200Hz - 1 wave "0", 2400Hz - 2 waves
”1") (Default)
2400 baud (2400Hz - 1 wave "0", 4800Hz - 2 waves
”1"), software-selected
(The tape recorder to be used may have to be speci¬
fied by the manufacturer when using 2400 baud)
o MODULATION
FSK (Frequency Shift Keying), software-controlled
O DEMODULATION
Software-controlled. The system software automatically
detects the baud rate upon receiving the data.
O MOTOR CONTROL
Available
o CONNECTOR
DIN 45326 (8 pins)
15
MSX HARDWARE SPECIFICATIONS
O TABLE OF SIGNAL PINS
1 PIN
1 NO.
[ SIGNAL
1 NAME
1 1
[DIRECTION 1
PIN CONNECTION
i
i
|
1 1
i
! 1
1
1 GND
\ 1
i
i
1 2
i
t GND
I 1
i
i
i
.
L
1 "l
1 1
__
1 3
1
1 GND
1 1
i
i
i 4
l-
1 5
i
1 CMTOUT
—f-
1
1 CMTIN
+ i
l i
1 OUTPUT 1
-H-H
1 1
f INPUT 1
/ ® ® \
\ © ® I
© y
i
i
i
i
i
i
1 6
1
1 REMOTE +
1 1
1 OUTPUT 1
i
i
i
1 7
1
1 REMOTE -
1 1
1 OUTPUT [
i
i
i
1 8
1
1 GND
1 1
i
i
16
MSX HARDWARE SPECIFICATIONS
o SAVE Level
The constants in the SAVE circuit should be adjusted so as to
perform the output level as follows:
Output level -45 dBm ± 5 dBm (0 dBm = 0.775 V)
The output should be 22 mVp-p ~ 7 mVp-p at 1200 Hz input signal.
o Sample Circuit for SAVE
, c -j|-
4.7k Q
Standard Value (*)
Output to CMT
4.7kfl
0.022^F I lOOfl
iw ifrr
o Frequency Characteristics
Lower Cutoff Frequency (*) Higher Cutoff Frequency
* Note that the lower cutoff capacitor is to protect the IC of MSX.
Cassette tape recorders themselves will not be harmed even if
it is not there. The capacitance may be in the range 0.1 ~ 2.2//F.
Adjust the capacitor to limit the lower cutoff frequency in the
range 16 “ 200Hz, if the output inpedance of the IC is too high.
17
MSX HARDWARE SPECIFICATIONS
1.4.2 Floppy Disk Interface
o The Floppy Disk Interface contains 16K bytes of ROM beginning
at 4000H that includes the following modules:
* MSX-DOS KERNEL
* MSX DISK BASIC
* PHYSICAL DISK I/O DRIVER (Supplied by manufacturer)
o The hardware interface is not specified. The physical disk
I/O driver supplied by the manufacturer should resolve the
hardware differences.
o Ideally, the mechanism in the disk drive should detect that the
drive door has been opened. This reduces the number of disk
accesses required to
Floppy disk format:
check if the system
MS-DOS compatible
disk
been replaced.
8-inch
Single-density
128
Bytes/Sector
8-inch
Double-density
1024
Bytes/Sector
5.25-inch
Double-density
512
Bytes/Sector
3.5-inch
CFD
512
Bytes/Sector
3-inch
CFD
512
Bytes/Sector
18
MSX HARDWARE SPECIFICATIONS
1.4.3 Printer Interface
o SPECIFICATIONS
8 bit parallel, handshakes by BUSY and STROBE
o LEVEL
TTL
O CHARACTER CODES
Same as the MSX display codes
O CONNECTOR
14-pin AMP compatible
o LIST OF PINS
19
MSX HARDWARE SPECIFICATIONS
1.4.4 RS-232C Interface
O LSI COMPONENTS
i-8251 Communications Interface
i-8253 Programmable Interval Timer
At least 4K bytes of ROM is required for software support.
o PORT ADDRESSES
80H R/W 8251 Data Port
81H R/W 8251 Command/Status Port
82H R Status Sense Port for CTS, Timer/Counter 2, RI, and CD
82H W Interrupt Mask Register
83H Reserved
84H R/W 8253 Counter 0
85H R/W 8253 Counter 1
86H R/W 8253 Counter 2
87H W 8253 Mode Register
* The port at address 83H is reserved for use by the manufacturer.
20
MSX HARDWARE SPECIFICATIONS
o USING THE PORT AT ADDRESS 82H
82H Read: Get System Status
r—
L_
Data
Bit
i
1
Description
1
1
D7
i
CTS (Clear To Send)
- —-1
1
1
0: CTS Asserted
1
1
1: CTS Negated
1
D6
1
Timer/Counter Output-2
from i8253 1
D5
"“1
1
D4
1
1
1
D3
1
1 Reserved
1
D2
.... J
1
D1
1 +
RI (Ring Indicator)
1
1
0: RI Asserted
1
t
1: RI Negated
1
DO
1 +
CD (Carrier Detect)
1
1
0: CD Asserted
1
1
1: CD Negated
1
l _
_ _
NOTE: The signals with the plus (+) sign are optional.
If only one signal is chosen, it must be 1 CD'.
NOTE
The CTS signal is sensed through the port
instead of through the 8251 because of a
problem in the CTS logic in some versions
of the 8251. Software handling is thus
made possible.
21
MSX HARDWARE SPECIFICATIONS
82H Write: Interrupt Mask Register
Data
Bit
Description
D7
D6
D5
D4
D3
D2
D1
DO
I
I Reserved
_J
Timer Interrupt from i8253 channel-2
1: Mask Interrupt (Initial value)
0; Enable Interrupt
Sync character detect/Break detect
1: Mask Interrupt (Initial value)
0: Enable Interrupt
Transmit Data Ready (Tx Ready)
1: Mask Interrupt (Initial value)
0: Enable Interrupt
Receive Data Ready (Rx Ready)
1: Mask Interrupt (initial value)
0: Enable Interrupt
NOTE: The signals above with the plus (+) sign are optional.
The minimum requirement for the interrupt signal is
thus Rx Ready.
22
MSX HARDWARE SPECIFICATIONS
o USING THE 8253 TO GENERATE BAUD RATE CLOCK FOR THE 8251
A. CRYSTAL FREQUENCY
The crystal frequency is 1.8432 MHz.
I----,
I Baud rate (Baud) I Scale Factor and Error (xl6) I
b -
--(-
—
-1
50
1
2304
1
75
1
1536
1
110
1
10 47
110.0287
+0.3%
1
150
1
768
1
300
1
3 84
1
600
1
192
1
1200
1
96
1
1800
1
64
1
2000
1
58
1986.2
-0.7%
1
2400
I
48
1
3600
1
32
1
4800
1
24
1
7200
1
16
1
9600
1
12
1
19200
1
6
1
_ ■ _
_j
B. USING THE COUNTER CHANNEL
CHO: Rx Baud rate clock
CHI: Tx Baud rate clock
CH2: Used by application (Interrupt generated optionally)
23
MSX HARDWARE SPECIFICATIONS
o PINS OF DB25 CONNECTOR
r-
i
h-
Pin
1 Signal
I
■
Pin
1
Signal
1
1 Frame Ground
1
14
1
2
1 Transmit Data
15
I
3
1 Receive Data
16
I
4
i Request To Send
17
1
5
1 Clear To Send
18
1
6
1 Data Set Ready
19
1
7
1 Signal Ground
20
1 Data
Terminal Ready
8
1 Carrier Detect
21
1
9
1
22
1 Ring
Indicator
10
1
23
1
11
1
24
1
12
1
25
1
13
1
1
I—
,
24
MSX HARDWARE SPECIFICATIONS
1.4.5 Peripheral I/O Port(s) (1 or 2)*
o LSI
AY-3-8910 compatible
o I/O
Input 4 bits, Output 1 bit, Bidirectional 2 bits per port
o LOGIC
Active high
o LEVEL
TTL
o CONNECTOR
9-pin AMP compatible
o LIST OF PINS
1 PIN
1 NO.
1 SIGNAL
i NAME
i
1 DIRECTION
r
PIN CONNECTION
1
1
1
1
i
1
1 1
1 FWD
1 Input
i
1
1
1 2
1
1 BACK
1
1 Input
“t
i
i
1
1
1
|
1 3
1
1 LEFT
i
1 Input
i
i
1
1
1
1
1 4
1
1 RIGHT
1
1 Input
i
i
\ (D (D ® ® ® 1
\ © © ® ® 1
1
1
1
i
1 5
1 *
1 + 5V
1
i
i
1
1
i
1 6
1
1 TRG 1
1 Input/
1 Output
i
i
1
1
1
1
1
1 " •*—*—
1
l
1
1
1 7
1
1 TRG 2
1
1 Output
l
i
i
i
1 8
l
1 OUTPUT
1
1 Output
i
i
1
1
1
1
1
1
T
1
1
1
1 9
1
1 GND
1
1
!
1
1
* Current capacity: 50mA each
25
MSX HARDWARE SPECIFICATIONS
o Circuit Diagram
All resistors are 10k ohm typically.
26
OOOOOOOOOfc ooooooooo
MSX HARDWARE SPECIFICATIONS
1.4.6 Joysticks
o There are two types of joysticks.
Joystick Type A has one trigger button, or if there is more
than one trigger button, the software cannot distinguish between
them.
Joystick Type B has two independent trigger buttons.
The joysticks produced from now on should show which type they
are and software that needs to have Type B should say so on the
package.
o Circuit Diagram
AMP
9PIN FWD
Option as described above.
27
MSX HARDWARE SPECIFICATIONS
1.4.7 Paddles
o A trigger pulse is sent to the 8 pin of the peripheral I/O port
every time the PDL function is called. The paddle circuit,
triggers the monostable multivibrator with this pulse. A pulse
of the length corresponding to the level of the volume is
returned to the port.
A maximum of 6 channels of paddles can be attached to each I/O
port.
Paddle timing diagram
FWDl
- # -
ta-td- -
- -r--—»-
r = 10^s to 3ms
Circuit diagram (for 1 channel)
NOTE: The volume (or the capacitance) should be adjustable as to
justify the function of the paddle.
28
MSX HARDWARE SPECIFICATIONS
1.4.8 Connectors
PIN CONNECTION
MSX HARDWARE SPECIFICATIONS
1.4.9 Slots
O CONCEPT OF SLOTS
For computers having 64K bytes of memory, the concepts of
slots and memory banking are nearly identical. The CPU can
directly choose the cartridge by its slot number.
The slot concept originated from a desire to support the maxi¬
mum amount of software. Using the slots, the software can be
run, regardless of the number of physical slots available to
the computer.
o ADVANTAGES OF SLOT STRUCTURE
In a common bus structure, when there is an even number of
memory banks, the device select signal connected to the bus
cannot distinguish between the different devices by using the
same memory area. If this were to occur, the system would not
only be unusable, but the hardware would quickly deteriorate.
By using the slot select signal to choose the memory devices,
the above problem is avoided, and programs that handle two or
more devices having the same memory area are made possible.
This is a favorable point, considering the system's flexibili¬
ty and expandability.
o Circuit diagram
RFSH
SlTSlo
SLTSL1
SLTSL2
STT5L3
30
MSX HARDWARE SPECIFICATIONS
1.5 Cartridges
1*5.1 Physical Cartridge Specifications
o Physical dimension of the standard cartridge
to
/-
o
v/v
| r~ -1
n
a-i
Oo
_ ;
( -
INSERT
DIRECTION
(FRONT)
1
7
o ,
r_ i i
t i
l
i
i
Vi_-1
i
_ )
109
o Physical dimension of the expanded cartridge
31
MSX HARDWARE SPECIFICATIONS
1.5.2 Cartridge Bus
o LIST OF SIGNAL PINS
r*“ ■
-1-
— T-
-r-
— T—
— —-
■"!
PIN
1
1
* i
PIN
1
1
*
1
NO.
1
NAME
1
I/O 1
NO.
1
NAME
1
I/O
1
i—
-+—
— H—
—
—i—
—
-+-
—
-4
1
1
CS1
i
0 1
2
1
CS2
1
0
1
3
1
CS12
i
0 1
4
1
SLTSL
1
0
1
5
1
Reserved #
i
- 1
6
1
RFSH
1
0
1
7
1
WAIT%
i
I 1
8
1
INT%
1
I
1
9
1
Ml
i
0 1
10
1
BUSDIR
1
I
1
11
1
IORQ
i
0 1
12
i
MERQ
I
0
1
13
1
WR
i
0 1
14
1
RD
1
0
1
15
1
RESET
i
0 1
16
1
Reserved #
1
-
1
17
t
A9
i
0 i
18
1
A15
i
0
1
19
1
All
i
0 1
20
1
A10
1
0
1
21
1
A7
i
0 1
22
1
A6
1
0
1
23
1
A12
i
0 i
24
1
A8
i
0
1
25
1
A14
i
0 f
26
1
A13
!
0
1
27
1
A1
i
0 I
28
1
A0
!
0
1
29
1
A3
i
0 t
30
1
A2
1
0
1
31
1
A5
t
0 1
32
1
A4
1
0
1
33
1
D1
i
I/O 1
34
1
DO
1
I/O
1
35
1
D3
i
I/O 1
36
1
D2
1
I/O
1
37
1
D5
i
I/O 1
38
1
D4
1
I/O
1
39
1
D7
i
I/O 1
40
1
D6
1
I/O
1
41
1
GND
i
- 1
42
1
CLOCK
1
O
1
43
1
GND
i
- 1
44
1
SWl
1
-
1
45
1
+5V
i
- 1
46
1
SW2
1
-
1
47
1
+5V
i
1
48
1
+12V
1
-
1
49
1
SOUNDIN
i
I 1
50
1
-12V
1
-
1
-X..
_ __1___
— 4—
— 4—
J
* The Input/Output directions are relative to the main unit.
# Do not use the Reserved PINs.
% OPEN COLLECTOR output
32
MSX HARDWARE SPECIFICATIONS
o LIST OF SIGNAL PINS
1 PIN NO.1
U- __
NAME
1 DESCRIPTION
1 1
CS1
ROM 4000 to 7FFF, selected signal
1 2
CS2
ROM 8000 to BFFF, selected signal
1 3
CS12
ROM 4000 to BFFF, selected signal
(for 256K ROM)
1 4
SLTSL
Slot select signal
1 5
Reserved
Reserved for future expansion. Do
not use this pin.
1 6
RFSH
Refresh signal
1 7
WAIT
Wait signal to CPU
1 8
INT
Interrupt request signal
1 9
Ml
Fetch cycle signal of CPU
1 10
BUSDIR
This signal controls the direction
of the external data bus buffer when
the cartridge is selected. It
is LOW when the data is sent by the
cartridge.
1 11
IORQ
I/O request signal
l 12
MERQ
Memory request signal
1 13
WR
Write signal
1 14
RD
Read signal
1 15
RESET
System reset signal
1 16
Reserved
Reserved for future expansion. Do
not use this pin.
1 17 ~3 2
A0~A15
Address bus
1 33"40
D0~D7
Data bus
1 41
GND
Ground
1 42
CLOCK
CPU clock, 3.57 9 MHz
1 43
GND
Ground
1 44, 46
SW1, SW2
Detect Insert/Remove for protection
1 45, 47
+5V
+5V power supply
1 48
+12V
+12V power supply
1 49
SOUNDIN
Sound input (-5 dbm)
l 50
-12V
-12V power supply
NOTE
The CS signals imply a memory
request and a read signal.
Thus they cannot be used as
chip select for writable
devices such as RAMs.
33
MSX HARDWARE SPECIFICATIONS
1.5.3 Cartridge Bus Connection Conditions
o FAN-IN, FAN-OUT (LS-TTL load)
Data and Address bus
Main unit 4 -
Below 2
(Fan-in) <
Above slot 1
(Fan-out) - >
O CONTROL SIGNALS
Above slot 2 I Below 2
- > I - >
(Fan-out) I (Fan-in)
- »
Above 5
4 -
Below 1
- >
o VOLTAGE LEVEL
TTL level
1.5.4 Cartridge Power Capacity
+5V
300 mA/slot
+12V
50 mA
-12V
50 mA
Cartridge
(Fan-out)
(Fan-in)
34
MSX HARDWARE SPECIFICATIONS
1.5.5 Sample Circuit Diagram of Expanded Slot Select Signal
Expanded slot adapter
(access to FFFF) ■ RD-SLTSEL
Al * A « SLTSL
MSX HARDWARE SPECIFICATIONS
1.6 Notes for System Expansion
1.6.1 RAM Expansion
o Since MSX-BASIC needs a contiguous RAM area from 8000 to FFFF,
the additional RAM should be added to the existing RAM so as
to be contiguous.
o Since the MSX-BASIC software requires only RAM from 8000 to
FFFF, RAM installed from 0000 to 7FFF cannot be used by it.
1.6.2 Slot Expansion
o When slots are expanded, the expanded slots must be expanded
from a primary slot. Primary slots are those slots managed by
the slot select register provided in port A of the 8255.
Thus, to select an expansion slot, first select the primary
slot to which the expansion slot is connected, then select the
desired slot.
o The slots directly attached to the MSX computer itself must be
primary slots. Because there are significant differences
between the primary and secondary slots, there must be a clear
indication of which kind of slot is placed in an expansion
adapter.
o The location of the slot select register for the additional
slots is address FFFF of the primary slot. To make it
possible to differentiate the register from ordinary RAM, take
the complement of the output of the register. That is, when
the register is read, the data is the complement of the value
of the register.
o A maximum of four cartridges can be connected to the cartridge
bus. Therefore, buffers are necessary if the system is to
support more than five slots. The BUSDIR signal controls the
direction of those buffers. Devices placed in expansion slots
that send signals to the CPU must also send the BUSDIR signal
to change the direction of the expansion slots to the CPU.
However, for memory accesses, it is possible to determine the
direction of the bus by using the slot select signal sent to
the primary slot, the memory request signal, and the read/
write signal. The direction of the buffer should thus be
controlled around the buffer circuit; cartridges containing
only ROM or RAM thus do not have to manage the BUSDIR signal,
and expansion RAM cartridges do not have to be expensive.
Cartridges containing devices to send signals to the CPU
(those devices responding to the INP instruction or supplying
an address in response to mode 2 interrupts) must force BUSDIR
to the 'L' level when sending data to CPU.
36
MSX HARDWARE SPECIFICATIONS
1.6.3 I/O Expansion
o In Z-80 based system, it is common to place I/O devices in the
I/O address space. Since the MSX system was designed to be
flexible and expandable, it is possible to add I/O devices
using cartridges that share the same address space. If this
is the case, those devices will not be able to be accessed
properly.
To avoid the above situation, the I/O devices should be placed
in the memory area because they will be managed by slot select
logic and the memory cannot be accessed simultaneously when
placed in different slots, since devices placed in the memory
area cannot be accessed by software running in different
slots. General devices such as the VDP must therefore be
placed in the I/O address space. Note also that in some cases
it is more economical to use the I/O address space, because
only eight bits of address information have to be decoded.
The MSX system specifications define the system device I/O
address space to be addresses from 40 to FF. The addresses
below 3F are left free. While other devices may use this
address space, other manufacturers may use the same addresses
for other purposes. Thus, we recommend that memory addresses
be used instead of the I/O area. In later MSX versions it
is possible that standard devices will use the unassigned
(reserved) addresses.
37
MSX HARDWARE SPECIFICATIONS
1.7 Address Maps
1.7.1 Memory Map
o The following is an example memory map.
FFFF
C000
8000
4000
0000
CPU
Memory
area
f--^
RAM
f-H
I DISK
Soft¬
ware I
t--4
t-1
i->
f--I
t-H
I BASIC I
I Expan I
I sionl
h-^
I—.- 1
0 1 2* 3*
System Cartridge
slot slot
o MSX BASIC uses the largest contiguous available RAM area
installed from 8000 to FFFF for its system working RAM area.
This RAM may be placed in any slot, including the expansion
si ot s.
o The slot select register, port A of the 8255, maps the physical
memory space to the logical CPU memory space in 16K-byte units
(pages). For example, the following value in the slot select
register allocates pages 0 and 1 from slot 0, page 2 from slot
2, and page 3 from slot 0.
(MSB) 76 54 32 10 (LSB)
1001101001001
I I I I
I I I *-— Allocate
i j i-Allocate
[ L - Allocate
(.-Allocate
The physical memory is always allocated to the same memory
page in the CPU memory space. It is not possible to allocate
it to a different page, as in allocating page 3 of slot 3 to
page 0 of the CPU memory space.
slot 0 for page 0
slot 0 for page 1
slot 2 for page 2
slot 0 for page 3
38
MSX HARDWARE SPECIFICATIONS
o The minimum system must have two slots, one for the system,
and the other for the cartridge.
NOTE
The meaning of "slot" does not
imply that it must have a car¬
tridge connector; however, the
cartridge slot must have the
cartridge connector.
39
MSX HARDWARE SPECIFICATIONS
1.7.2 I/O Address Map
FF
F8
F7
FO
EO
D8
DO
CO
B8
B5
B4
BO
A8
AO
98
90
88
80
40
00
Audio/Video Control
ROM for Chinese
Characters
Floppy Disk Controller
Light Pen Interface
Calendar Clock
External Memory
PPI (8255)
PSG (AY-3-8910)
VDP (9918A)
Printer Interface
—i
RS-232C Interface
Reserved
Unspecified
40
MSX HARDWARE SPECIFICATIONS
1.7.3 Printer Port
90H
R
Busy state:
Bit 1
90 H
W
Strobe output:
Bit 0
91H
W
Print data
1.7.4
VDP
Port
98H
R/W
Video RAM data
99H
R/W
Command and status register
1.7.5
PSG
Port
AOH
W
Address latch
A1H
w
Data write
A2H
R
Data read
1.7.6
PPI
Port
A8H
R/W
Port A
A9H
R/W
Port B
AAH
R/W
Port C
ABH
R/W
Mode register
1.7.7 External Memory (Sony)
BOH thruogh B3H
1.7.8 Light Pen (Sanyo)
B8H through BBH
41
MSX HARDWARE SPECIFICATIONS
1.7.9 Audio/Video Control
F7H W BIT4 - AV Control
W BIT5 - Ym Control
W BIT6 - Ys Control
W BIT7 - Video select
L - TV
L - TV
L - Super
L - TV
1.7.10 Notes on I/O Address Assignments
o I/O addresses 40-FF are assigned for system use. The unused
empty area is also reserved for system use.
Although I/O addresses are defined above, the software must
not access those devices directly using the above ports. All
I/O accesses must be done using BIOS calls, in order to make
the software independent of hardware differences. MSX
manufacturers may change some of the hardware from the
standard MSX system and maintain software compatibility by
rewriting BIOS. The hardware differences would thus be trans¬
parent to the software.
The only exception to the above is the access to the VDP.
Locations 6 and 7 of the MSX system ROM contains the Read and
Write addresses of the VDP register. Software that must
access the VDP quickly may access the VDP directly by using
the addresses stored in ROM.
o Addresses 00 to 3F are free. Different devices using the same
address must not be accessed simultaneously. in general, the
I/O devices that are not defined here should be placed in the
memory space as memory-mapped I/O. See section 1.6.3 for fur¬
ther details.
% The FDC may be placed in the I/O area; however, it must have
a mechanism to disable it, and it must be enabled only if the
system does accesses to the FDC. This makes it possible for
the system to have more than one FDC interface for handling
different media types.
42
MSX HARDWARE SPECIFICATIONS
1.7.11 8255 (PPI) Bit Assignments
I PORT
I 5
SIGNAL
NAME
CSOL
CSOH
CS1L
CS1H
CS2L
CS2H
CS3L
CS3H
CASON
CASW
CAPS
SOUND
DESCRIPTION
0000-3FFF Address slot select signal
4000-7FFF Address slot select signal
8000-BFFF Address slot select signal
C000-FFFF Address slot select signal
Keyboard return signal
Keyboard scan signal
Cassette control signal (L=ON)
Cassette write signal
CAPS lamp signal (L=ON)
Software-controlled sound output
43
MSX HARDWARE SPECIFICATIONS
1.7.12 PSG Bit Assignments
r"
i
i.
PORTI
BIT
1
I/O
1
CONNECTOR PIN NO.
1
NOTES
A
t
0
1
1
J3-PIN 1
#1 1
FWD1
1
1
1
J4-PIN 1 *
#2 1
FWD2
1
1
1
I
1
J3-PIN 2
#1 1
BACK1
1
1
1
J4-PIN 2 *
#2 1
BACK2
1
2
1
N
1
J3-PIN 3
#1 1
LEFT1
1
1
1
J4-PIN 3 *
#2 1
LEFT2
1
3
1
P
1
J3-PIN 4
#1 1
RIGHT1
1
1
1
J4-PIN 4 *
#2 1
RIGHT2
1
4
1
U
1
J3-PIN 6
#1 1
TRGA1
1
1
1
J4-PIN 6 *
#2 1
TRGA2
1
5
1
T
1
J3-PIN 7
#1 1
TRGBl
1
1
1
J4-PIN 7 *
#2 1
TRGB2
1
6
1
1
KEY LAYOUT Select
#4 1
Japanese
1
1
1
1
version only
1
7
1
1
CSAR
1
t
1
1
(Cassette tape READ) 1
B
1
0
1
1
J3-PIN 6
#3 1-
-
1
1
1
0
1
J3-PIN 7
#3 1
1 "H" Level
1
2
1
0
1
J4-PIN 6 *
#3 i
1
1
3
1
T
l
J4-PIN 7 *
#3 1-
-
1
4
1
P
1
J3-PIN 8
1
1
5
1
U
1
J4-PIN 8 *
1
1
6
1
T
1
PORT A INPUT SELECT I
Selects J3 or J4
1
7
1
t
KLAMP
1
Japanese
1
1
1
(KANA LAMP L=ON)
1
version only
L-
_
_ j__
_ _
- J—
__
_ _| _
.
_i _
#1 Available if bit 6 of port B is LCW and is used by J0YSTICK1
#2 Available if bit 6 of port B is HIGH and is used by J0YSTICK2
#3 Set these pins to "H" when using them as an input port.
Connect an open collector buffer to the output.
#4 JIS layout - "H", syllable layout - "L"
<Remark> PIN 5: +5V
PIN 9: GND
o On the minimum MSX system, there is no J4 connector.
44
PART B
MSX SYSTEM SOFTWARE
MSX BASIC REFERENCE GUIDE
2. Language Specifications
2.1 MSX-BASIC Reference Guide
MSX-BASIC is an extended version of Microsoft Standard BASIC
Version 4.5, and includes support for graphics, music, and various
peripherals attached to MSX Personal Computers. Generally, MSX-
BASIC is designed to follow GW-BASIC, which is one of the standard
BASICS running on 16-bit computers. During the creation of MSX-
BASIC, a major effort was made to make the system as flexible and
expandable as possible.
MSX-BASIC also features a BCD-arithmetic function with a double¬
precision accuracy of up to 14 digits. Arithmetic operations thus
do not generate rounding errors that tend to confuse new program¬
mers. In addition, all trancendental functions are calculated
with 14-digit accuracy. 16-bit, signed, integers are also availa¬
ble for faster execution.
2.1.1 Modes of Operation
When MSX-BASIC is initialized, it displays the "OK" prompt.
"Ok" indicates MSX-BASIC is at command level; that is, it is ready
to accept commands. At this point, MSX-BASIC may be used in
either of two modes: direct mode or indirect mode.
In the direct mode, MSX-BASIC statements and commands entered as
they are without preceeding line numbers. They are executed imme¬
diately, and the results of arithmetic and logical operations may
thus be determined quickly. While these results may also be
stored for later use, the instructions themselves are lost after
execution. Direct mode is thus useful for debugging and for using
MSX-BASIC as a "calculator" for quick computations not requiring
a complete program.
The indirect mode is used for entering programs. Program lines are
preceded by line numbers and are stored in memory. The program
stored in memory is executed by entering the RUN command.
46
MSX BASIC REFERENCE GUIDE
2.1.2 Line Format
The program lines of MSX-BASIC programs must be in the following
format. Square brackets denote statements that are optional.
nnnnn BASIC statement[:BASIC statement...] <Carriage Return>
An MSX-BASIC program line always begins with a line number and
ends with a carriage return. A logical line may contain a maximum
of 255 characters. More than one BASIC statement may be placed on
a logical line, but the statements must be separated by a colon.
The line numbers indicate the order in which the program lines
will be stored in memory, and in MSX-BASIC, they must be between 0
and 65529. They are also used as references during branching and
editing.
During editing, a period (.) may be used with the LIST, AUTO, and
DELETE commands to refer to the current line.
2.1.3 Character Set
The MSX-BASIC character set consists of alphabetic characters,
numeric characters, special characters, graphic characters, and
both (Japanese) hiragana and katakana characters. See section
5.2.2 for details.
The alphabetic characters in MSX-BASIC are the uppercase and
lowercase letters of the alphabet.
The MSX-BASIC numeric characters are the digits 0 through 9.
In addition, the following special characters are recognized by
MSX-BASIC:
Character Action
Blank
~ Equals sign or assignment symbol
+ Plus sign
Minus sign
* Asterisk or multiplication symbol
/ Slash or division symbol
Up arrow or exponentiation symbol
( Left parenthesis
) Right parenthesis
% Percent
# Number (or pound) sign
$ Dollar sign
I Exclamation point
[ Left bracket
] Right bracket
, Comma
. Period or decimal point
47
MSX BASIC REFERENCE GUIDE
&
?
<
>
¥
<Rubout>
<Escape>
<Tab>
<Line feed>
<Carriage
return>
Single quotation mark (apostrophe)
Semicolon
Colon
Ampersand
Question mark
Less than
Greater than
Yen sign or integer division symbol
(back slash in international versions)
At sign
Underscore
Deletes last character typed.
Escapes
Moves print position to next tab stop.
Tab stops are set every eight columns.
Moves to next physical line.
Terminates input of a line.
2.1.4 Constants
Constants are the values MSX-BASIC uses during execution. There
are two types of constants: string and numeric.
A string constant is a sequence of up to 255 alphanumeric
characters enclosed in double quotation marks.
Examples:
"HELLO"
"$25,000.00"
"Number of Employees"
Numeric constants are positive or negative numbers. MSX-BASIC
numeric constants cannot contain commas. There are six types of
numeric constants:
1. Integer constants Whole numbers between -32768 and 32767.
Integer constants do not contain decimal
points.
2. Fixed-point
constants
Positive or negative real numbers, i.e.,
numbers that contain decimal points.
3. Floating-point Positive or negative numbers represented
constants in exponential form (similar to scientific
notation). A floating-point constant
consists of an optionally signed integer
or fixed-point number (the mantissa)
followed by the letter E and an optionally
signed integer (the exponent). The
allowable range for floating-point
constants is 10E-64 to 10E+63.
48
MSX BASIC REFERENCE GUIDE
Examples:
235.988E-7 = .0000235988
2359E6 =2359000000
(Double-precision floating-point constants
are denoted by the letter D instead of E.)
4. Hex constants
5. Octal constants
6. Binary constants
Hexadecimal numbers, denoted by the
prefix &H.
Examples:
&H7 6
&H3 2F
Octal numbers, denoted by the prefix &0.
Examples:
&0347
&01234
Binary numbers, denoted by the prefix &B.
Examples:
&B01110110
StBlllOOlll
o Single- And Double-Precision Numeric Constants
Numeric constants may be either single-precision or double¬
precision numbers. Single-precision numeric constants are stored
with 6 digits of precision, and are printed with up to 6 digits of
precision. Double-precision numeric constants are stored with 14
digits of precision and printed with up to 14 digits. Double¬
precision is the default for constants in MSX-BASIC.
A single-precision constant is any numeric constant that has one
of the following characteristics:
1. Exponential form using E.
2. A trailing exclamation point (!).
Examples:
-1.09E-06
22.51
A double-precision constant is any numeric constant that has one
of these characteristics:
49
MSX BASIC REFERENCE GUIDE
1. Any digits of number without any exponential or type
specifier.
2. Exponential form using D.
3. A trailing number sign (#).
Examples:
3489
345692811
-1.0943 2D-06
3489.0#
7654321.1234
2.1.5 Variables
Variables are names used to represent values used in a BASIC
program. The value of a variable may be assigned explicitly by
the programmer, or it may be assigned as the result of
calculations in the program. Before a variable is assigned a
value, its value is assumed to be zero.
o Variable Names And Declaration Characters
MSX-BASIC variable names may be of any length. Up to 2 characters
are significant. Variable names can contain letters and numbers;
however, the first character must be a letter. Special type
declaration characters are also allowed—see the discussion below.
A variable name may not be a reserved word and may not contain
embedded reserved words. Reserved words include all MSX-BASIC
commands, statements, function names, and operator names (See
appendix for the list). If a variable begins with FN, it is
assumed to be a call to a user-defined function.
Variables may represent either a numeric value or a string. String
variable names are written with a dollar sign ($) as the last
character, for example: A$ = "SALES REPORT".
The dollar sign is a variable type declaration character; that is,
it "declares" that the variable will represent a string.
Variable names may also inherently declare the variables to be
integer, single-precision, or double-precision. The last
character in these variables must be one of the following
variable-type declaration characters:
% Integer variable
I Single-precision variable
# Double-precision variable
The default type for a numeric variable name is double-precision.
50
USX BASIC REFERENCE GUIDE
Examples of MSX-BASIC variable names:
PI# Declares a double-precision value.
MINIMUM! Declares a single-precision value.
LIMIT% Declares an integer value.
N$ Declares a string value.
ABC Represents a double-precision value.
Variable types may also be declared within a program by using the
MSX-BASIC DEFINT, DEFSTR, DEFSNG, and DEFDBL statements. For de¬
tails, refer to the descriptions of these statements.
o Array Variables
An array variable is a group or a table of values that is organi¬
zed with the same variable name. Each element in an array is ref¬
erenced by an array variable (having an integer or an integer ex¬
pression as a subscript). Names for array variables may have as
many subscripts as there are dimensions in the array. For example,
V(10) would be the name of a variable in a one-dimension array,
T(l,4) would be the name of a variable in a two-dimension array,
and so on. MSX-BASIC supports a maximum number of 255 dimensions
for an array. The maximum number of elements depends on the size
of the computer's memory.
o Space Requirements
The following table lists the number of bytes that each variable
occupies in memory.
Variables: Type Bytes
Integer 2
Single-Precision 4
Double-Precision 8
Arrays: Type Bytes
Integer 2 per element
Single-Precision 4 per element
Double-Precision 8 per element
Strings: 3 bytes for bookkeeping plus the length of the
string.
2.1.6 Type Conversion
When necessary, MSX-BASIC will convert a numeric constant from one
type to another. The following rules and examples should be kept
in mind.
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MSX BASIC REFERENCE GUIDE
1. If a numeric constant of one type is set to a numeric vari¬
able of a different type in a LET statement, the number is
converted and stored as the type declared by the new varia¬
ble name, unless an attempt to set a string variable to a
numeric variable is done. The latter case results the oc¬
currence of a "Type mismatch" error.)
Example:
10 A%=23.42
20 PRINT A%
RUN
23
2. During the evaluation of an expression, all operands of the
arithmetic or relational operation are converted to a uni¬
form precision to match the most precise operand. The op¬
eration also results in the precision of the most precise
operand.
Examples:
10 D=6/71
20 PRINT D
RUN
.857142 85714286
The operation was done in double-
-precision and the result, returned
in D, is double-precision.
10 D! =6 / 7
20 PRINT D!
RUN
.857143
The operation was done in double-
-precision and the result, returned
to DI (a single-precision variable)
was rounded and printed as single¬
precision.
3. Logical operators convert their operands to integers and
return integer results. Operands must be between -32768
and 32767, or an "Overflow" error occurs.
4. When a floating-point value is converted to an integer, the
fractional portion is truncated.
Example:
10 C%=55.88
20 PRINT C%
RUN
55
5. If a double-precision variable is set to a single-preci¬
sion value, only the first six digits of the double-preci¬
sion are valid. Single-precision variables support only a
maximum of six digits.
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MSX BASIC REFERENCE GUIDE
Example:
10 Ai =SQR(2)
20 B=A1
30 PRINT AI,B
RUN
1.41421 1.41421
2.1.7 Expressions and Operators
An expression may be a string or numeric constant, a variable, or
a combination of constants and variables with operators which
produces a single value.
Operators perform mathematical or logical operations on values.
MSX-BASIC operators may be divided into four categories:
1. Arithmetic
2. Relational
3. Logical
4. Functional
These categories will be described in the following sections,
o Arithmetic Operators
Arithmetic operators in MSX-BASIC have a defined order of prece¬
dence. The operators are listed below in order of precedence.
Operator
Operation
Example
a
Exponentiation
X
<
X
-
Negation
-X
*,/
Multiplication, Floating¬
point Division
X*Y
X/Y
+ r~
Addition, Subtraction
X+Y
To change the above order of evaluation of operations, use paren¬
theses. The operations embedded within parentheses will be evalu¬
ated first. Within the parentheses themselves, the above evalua¬
tion order is followed.
o Integer Division And Modulus Arithmetic
The following two additional operations, integer division and mod¬
ulus arithmetic, are also available in MSX-BASIC:
Integer division is denoted by the yen symbol (or the backslash in
international versions). The operands are truncated to integers
(between -32768 and 32767) before division is done. The quotient
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MSX BASIC REFERENCE GUIDE
is truncated to an integer.
Examples:
10¥4=2
25.6 8¥6.99=4
Integer division follows both multiplication and floating-point
division in the above order of precedence.
Modulus arithmetic is denoted by the operator MOD. Modulus
arithmetic yields the (integer) remainder of integer division.
Example:
10.4 MOD 4=2 (10/4=2 with a remainder of 2)
25.68 MOD 6.99=1 (25/6=4 with a remainder of 1)
Modulus arithmetic follows integer division in the above order of
precedence.
o Overflow Or Division By Zero
During the evaluation of an expression, if a division by zero is
attempted, a "Division by zero" message is displayed, and the ex¬
ecution of the program is terminated. Also, if an overflow occurs
during the evaluation of an expression, an "Overflow" message is
displayed and the execution of the program is terminated.
o Relational Operators
Relational operators are used to compare two values. The result of
the comparison is either "true" (-1) or "false" (0). The result
can then be used to make decisions for program logic. (See the
description on the "IF" statement.)
The relational operators are as follows:
Operator
Relationship
Exam pi
-
Equality
X=Y
<>
Inequality
XOY
<
Less than
X<Y
>
Greater than
X>Y
<=
Less than or
equal to
X<=Y
>=
Greater than
or equal to
X>=Y
(The equals sign is also used to assign a value to a variable.)
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MSX BASIC REFERENCE GUIDE
When both arithmetic and relational operators are used in a single
expression, the arithmetic operation is done first. For example,
X+Y<(T-1)/Z is true if the value of X + Y is less than the value
of T-l divided by Z.
More examples:
IF SIN(X)<0 GOTO 1000
IF I MOD JOO THEN K=K+1
o Logical Operators
Logical operators test multiple relationships, bit manipulation,
or Boolean operations. The logical operator returns a one-bit re¬
sult which is either "true" (not zero) or "false" (zero). Logical
operations are performed after arithmetic and relational opera¬
tions in expressions. The outcome of a logical operation is de¬
termined as shown in Table 1. The operators are listed in their
order of precedence.
Table 1. Truth Table of MSX-BASIC Relational Operators
NOT
X
1
0
AND
X
1
1
0
0
OR
X
1
1
0
0
XOR
X
1
1
0
0
EQV
X
1
1
0
0
NOT X
0
1
Y
1
0
1
0
X AND Y
1
0
0
0
Y
1
0
1
0
OR
1
1
1
0
Y
1
0
1
0
XOR
0
1
1
0
Y
1
0
1
0
X EQV Y
1
0
0
1
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MSX BASIC REFERENCE GUIDE
IMP
X Y X IMP Y
11 1
10 0
0 1 1
0 0 1
Besides using relational operators to make decisions on program
flow, logical operators can connect two or more relations and re¬
turn true or false to be used in decisions.
Examples:
IF D<200 AND F<4 THEN 80
IF I>10 OR K<0 THEN 50
IF NOT P THEN 100
Logical operators convert their operands to 16-bit, signed, two's
complement integers between -32768 and 32767. If the operands are
not in this range, an error results. If both operands are sup¬
plied as 0 or -1, the logical operators return 0s or -Is. The
given operation is done on the integers by the results of the cor¬
responding bits in the two operands.
It is thus possible to use logical operators to test bytes for a
particular bit pattern. For instance, the AND operator may be used
to "mask" bits of a status byte for an I/O port. The OR operator
may be used to "unmask" bits of a status byte for an I/O port.
The following are examples of how the logical operators work.
63 AND 16=16 63 = binary 111111, and 16 = binary 10000,
so 63 AND 16 =16.
15 AND 14=14 15 = binary 1111, and 14 = binary 1110,
so 15 AND 14 = 14 (binary 1110).
-1 AND 8=8 -1 = binary 1111111111111111, and 8 = binary 1000,
so -1 AND 8=8.
4 OR 2=6 4 = binary 100, and 2 = binary 10,
so 4 OR 2 = 6 (binary 110).
10 OR 10=10 10 = binary 1010,
so 1010 OR 1010 = 1010 (decimal 10).
-1 OR -2=-l -l = binary llllllllllllllll
and -2 = binary 1111111111111110,
so -1 OR -2 = -1.
The bit complement of sixteen zeros is sixteen ones
(the two's complement representation of -1).
NOT X=-(X+1) The two's complement of any integer is its bit
complement plus one.
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MSX BASIC REFERENCE GUIDE
o Functional Operators
In MSX-BASIC, functions are used in expressions to call previously
defined operations such as SQR (square root) and SIN (sine) for
use in evaluating operands. Some are resident functions provided
already in the MSX-BASIC interpreter.
Functions may also be defined within programs if they are not pro¬
vided with the MSX-BASIC system. These functions may be defined
by using the "DEF FN" statement. For a more detailed discussion,
refer to the descriptions for "DEF FN".
o String Operations
Two or more strings may be concatenated by using a plus sign (+).
Example;
10 A$=”FILE" ; B$="NAME"
20 PRINT A$+B$
30 PRINT "NEW "+A$+B$
RUN
FILENAME
NEW FILENAME
Two strings may also be compared by using the same relational op¬
erators used for numbers, as shown below:
= <><><=> =
Strings are compared by comparing the ASCII codes of both strings,
comparing one character at a time. If all of the ASCII codes are
the same, the strings are considered equal. If some of the ASCII
codes are different, the string having the ASCII code with the
lower code number will precede the other string. If the end of
one of the strings is reached before the end of the other string
is reached, the shorter string precedes the other string. During
comparison, leading and trailing spaces are significant.
Examples:
"AA"<"AB"
"FILENAME"="FILENAME"
"X&">"X# n
"CL ">"CL"
"kg">"KG"
"SMYTH“<"S MYTH E"
B$<" 9/12/ 83" where B $«" 8/12/ 83 "
Strings can thus be compared for alphabetization or for determi¬
ning branching of program logic. Note that when string variables
are compared, the expressions must be enclosed in quotation marks.
2.1.8 Program Editing
MSX-BASIC also includes a Full Screen Editor to allow the program¬
mer to enter program lines and edit them using the entire screen.
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MSX BASIC REFERENCE GUIDE
The MSX-BASIC Full Screen Editor supports special keys for moving
the cursor, for inserting or deleting characters, and for erasing
lines or screens. These time-saving special functions and their
key assignments will be discussed in the following sections.
With the Full Screen Editor, programmers can move the cursor any¬
where on the screen and make the necessary corrections. To make
changes, the cursor is placed on the first line to be changed, and
after the changes are entered, the <RETURN> key is pressed at the
beginning of each line. Lines in the stored programs will not be
changed unless a <RETURN> is entered somewhere within the line.
Writing Programs
When MSX-BASIC is used and the "Ok" prompt is issued, the system
is in the direct mode and is ready to receive a RUN command to ex¬
ecute the program or Editor commands. Except for commands to exe¬
cute programs, lines that are entered are processed by the Full
Screen Editor. All lines of text beginning with numbers are con¬
sidered as program statements. The Editor processes the program
statements in one of the following ways:
1. A new line is added to the program if the line number is
valid (between 0 and 65529) and at least one non-blank
character follows the line number.
2. An existing program line is modified if the line number
already exists in the program and at least one non-blank
character follows the line number. The new line replaces
the text of the previously existing line.
3. An existing program line is deleted if the line number
already exists in the program and the new line contains
only a line number.
4. An error is generated.
Am attempt to delete a non-existent line will result in an
"Undefined line number" error.
If the new line causes the program memory to be entirely
filled, no line is added and "Out of memory" is displayed.
More than one statement may be placed after a line number, except
the statements must be separated by colons (:). (These colons do
not require spaces.) A logical program line may have a maximum of
255 characters, including the line number.
Editing Programs
The LIST command displays all or a part of the program currently
residing in memory on the screen so that they can be edited with
the Full Screen Editor. To modify the program, move the cursor to
the location requiring change and do one of the following:
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MSX BASIC REFERENCE GUIDE
1. Type over existing characters
2. Delete characters to the right of the cursor
3. Delete characters to the left of the cursor
4. Insert characters
5. Append characters to the end of the logical line
These actions are performed by special keys assigned to the
Full Screen Editor (see the next section).
Program lines are changed if a carriage return is entered while
the cursor is located somewhere on the line. This action changes
all editing done to the logical line, regardless of the number of
physical lines the program line encompasses. The cursor can be
located anywhere in the program line.
Full. Screen Editor Functions
The following table lists the hexadecimal codes for the MSX-BASIC
control characters and summarizes their functions. The Control-key
sequence normally assigned to each function is also listed. These
conform as closely as possible to ASCII standards.
A discussion of the individual control follows the table.
Table 1. MSX-BASIC Control Functions. Control characters are
entered by holding down CTRL and pressing the character key.
Hex Control Special
Code Key Key Function
01 A
02 * B
03 * C
04 * D
05 * E
06 * F
07 * G
08 H Back Space
09 I Tab
0A * J
0B * K Home
0C * L CLS
0D * M Return
0E * N
OF * 0
10 * P
11 * Q
12 * R INS
Ignored
Move cursor to start of previous word
Break if MSX-BASIC is waiting for input
Ignored
Erase text to end of logical line
Move cursor to start of next word
Beep
Backspace, deleting characters passed over
Tab to next TAB stop
Line feed
Move cursor to home position
Clear screen
Carriage return (enter current logical
line)
Append at end of line
Ignored
Ignored
Ignored
Toggle between insert and typeover modes
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MSX BASIC REFERENCE GUIDE
13
*
S
Ignored
14
*
T
Ignored
15
*
U
Erase logical line
16
*
V
Ignored
17
*
W
Ignored
18
*
X
Select
Ignored
19
*
Y
Ignored
1A
*
Z
Ignored
IB
[
ESC
Ignored
1C
*
¥
Right arrow
Move cursor
right(back slash
ID
*
]
Left arrow
Move cursor
left
IE
*
A
Up arrow
Move cursor
up
IF
*
Down arrow
Move cursor
down
7F
DEL
DEL
Delete character at cursor
Note: The keys marked with asterisks (*) cancel the insert
mode if the Full Screen Editor is in insert mode.
PREVIOUS WORD
The cursor is moved left to the first character of the previ¬
ous word. A word is defined as a character string composed
of A- Z , a-z, or 0-9.
BREAK
Returns the control to MSX-BASIC direct mode without changing
the line that was being edited.
ERASE TO END OF LINE
The cursor is moved to the end of the logical line, and the
characters passed over are deleted. Additional characters
at the new cursor position are appended to the line.
NEXT WORD
The cursor is moved right to the first character of the next
word. A word is defined as a character string composed of
A-Z, a-z, or 0-9.
BEEP
Produces the beep tone.
BACKSPACE
Deletes the character to the left of the cursor. All
characters to the right of the cursor are moved to the left
one position. Any subsequent characters and lines within the
current logical line are moved up (wrapped).
TAB
TAB moves the cursor to the next tab stop, overwriting all
spaces. Tab stops occur every 8 characters.
CURSOR HOME
Moves the cursor to the upper left corner of the screen. The
screen is not erased.
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MSX BASIC REFERENCE GUIDE
CLEAR SCREEN
Moves the cursor to home position and clears the entire
screen, regardless of where the cursor is positioned when the
key is entered.
CARRIAGE RETURN
A carriage return ends the logical line and saves it as part
of the MSX-BASIC program.
APPEND
Moves the cursor to the end of the line, without deleting the
characters passed over. All characters typed at the new
position are appended to the logical line until a carriage
return is encountered.
INSERT
Toggle switch for insert mode. When insert mode is on, the
cursor size is reduced and characters are inserted at the
current cursor position. Characters to the right of the
cursor move right as new characters are typed. Line wrap
is done on characters going beyond the physical line. If
the insert mode is off, the size of cursor returned to
normal, and the typed characters replace any existing
characters on the line.
CLEAR LOGICAL LINE
Erases entire logical line when this key is entered anywhere
in the line.
CURSOR RIGHT
Moves the cursor one position to the right. Line wrap is
done on characters going beyond the physical line.
CURSOR LEFT
Move the cursor one position to the left. Line wrap is done
on characters going beyond the physical line.
CURSOR UP
Moves the cursor up one physical line at the current
position.
CURSOR DOWN
Moves the cursor down one physical line at the current
position.
o Logical line Definition with INPUT
A logical line ordinarily consists of all the characters on all of
its physical lines. During the execution of an INPUT or LINE
INPUT statement, however, this definition is modified slightly to
allow for formatted input. When either statement is executed,
the logical line is restricted to characters typed or passed over
by the cursor. The insert mode and the delete function only
move characters within the logical line, and DELETE decrements
the size of the line.
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MSX BASIC REFERENCE GUIDE
The insert mode increments the logical line, except when the
characters moved will write over non-blank characters that are on
the same physical line but not part of the logical line. If this
occurs, the non-blank characters that are not part of the logical
line are preserved, and the characters at the end of the logical
line are erased. This is to preserve labels existing prior to the
INPUT statement. If an incorrect character is entered as the line
is being typed, it can be deleted using the <Back Space> key or
with a Control-H. Once the undesired character(s) have been
deleted, simply continue typing the line.
To delete the current line being typed, type Control-U.
To correct program lines of the program currently in memory,
simply type a new line using the same line number. MSX-BASIC will
automatically replace the old line with the new line.
To delete the entire program currently in memory, enter a NEW
command. Usually the NEW command is only used to clear the memory
before entering a new program.
2.1.9 Special keys
MSX-BASIC supports several special keys (function keys and the
STOP key) as follows.
o Function Keys
MSX-BASIC has ten predefined function keys. The current settings
of these keys are displayed on the last line on the screen and can
be redefined within a program with the KEY statement. The initial
settings for the keys are as follows:
FI
color [b]
F2
auto lb]
F4
goto lb]
F5
list lb]
F5
runIcr]
F6
color 15,4,7Icr]
F7
cload"
F8
cont(cr]
F9
list.Lcr1lu] Cu]
F10
Ids] run lcr ]
Meanings of abbreviations:
[b] = blank character
tcr]= carriage return
[ul = cursor up character
lcls]=clear screen character
( F6 color 15,4,4[cr]
in international versions)
The function keys can also be used as event trap keys. Refer to
the ON KEY GOSUB and KEY ON/OFF/STOP statements for details.
o STOP key
When MSX-BASIC is in the direct mode, the STOP key has no effect
on the current operation, and MSX-BASIC simply ignores its input.
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USX BASIC REFERENCE GUIDE
If MSX-BASIC is executing a program and the STOP key is pressed,
program execution is suspended and the cursor is displayed to
indicate that execution was suspended. If the STOP key is pressed
again, execution is resumed. If the CTRL key is held down and the
STOP key is pressed, MSX-BASIC stops executing the program and
returns to the direct mode with the following message.
Break in nnnn
The nnnn is the line number of the program that was being executed
when the execution was aborted.
2.1.10 ERROR MESSAGES
If an error is encountered during program execution, execution
terminates, and the appropriate error message is displayed. Refer
to 2.1.17 for a complete list of MSX-BASIC error codes and error
messages.
2.1.11 Commands and Statements except those doing I/O
AUTO [<line number>[,<increment>]3
Automatically generates line numbers after each carriage
return.
AUTO begins numbering at <line number> and increments each
subsequent line number by <increment>. The default for both
values is 10. If <line number> is followed by a comma and
<increment> is not specified, the last increment specified in
an AUTO command is assumed.
If AUTO generates an existing line number, an asterisk is
printed after the line number as a warning that the existing
line will be replaced. If a carriage return is instead
immediately entered, the existing line is preserved and the
next line number is generated.
The AUTO command is terminated by typing Control-C or Control-
STOP, and MSX-BASIC returns to the direct mode. The line being
input when Control-C is typed is not saved.
CONT
Continues program execution after a BREAK or STOP.
DELETE Kline number>3 [-<line numberM
Deletes program lines.
BASIC always returns to the direct mode after a DELETE is
entered. If the Cline number> does not exist, an 'Illegal
function call' error occurs.
LIST Kline number>[-Kline number>]]]
Lists all or a part of the program.
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MSX BASIC REFERENCE GUIDE
If both <line number> parameters are omitted, the program is
listed beginning at the lowest line number.
If only the first Cline number> parameter is specified, only
that line is listed.
If the first Cline number> parameter and a are specified,
that line and all lines following it are listed.
If and the second Cline number> parameter are specified,
all lines beginning at the lowest line number are listed until
the specified number is reached.
If both Cline number> parameters are specified, the lines in
the range from the first Cline number> through the second
Cline number> are listed.
The displayed listing can be terminated by holding down "CTRL 1 '
and pressing the "STOP" key. The listing can be temporarily
suspended by pressing the "STOP" key, and resumed by pressing
the "STOP" key again.
LLIST [Cline number>I-[Cline number>]]]
Lists all or part of the program on the printer, with the use
of the parameters being identical for the LIST command.
NEW
Deletes the current program in memory and resets all variables.
RENUM [[Cnew number >H, [Cold number>] [, Cincrement>] ] ]
Renumbers program lines.
The Cnew number> parameter is the first line that will be used
in the renumbered program, with the default being 10. The Cold
number> is the line of the current program where renumbering is
to begin, with the default being the first line of the program.
The Cincrement> is the increment used in renumbering, and the
default is 10.
RENUM also changes all line number references following GOTO,
GOSUB, THEN, ELSE, ON..GOTO, ON..GOSUB and ERL statements to
reflect the new line numbers. If a nonexistent line number
appears after one of the above statements, an 'Undefined
line nnnn in mmmm 1 is displayed. The reference to the
incorrect line number (nnnn) is not changed by RENUM, but line
number mmmm may be changed.
NOTE: RENUM can neither be used to change the order of program
lines (for example, entering RENUM 15,30 for a program having
the three lines numbered 10, 20 and 30), nor can it be used to
generate line numbers greater than 65529. In either case, an
'Illegal function call' error results.
RUN [Cline number>]
Executes the current program.
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USX BASIC REFERENCE GUIDE
Execution begins at the first line of the program unless the
<line number> parameter is specified, in which case, execution
begins at that line.
TRON/TROFF
Traces the execution of program statements.
The TRON statement can be executed in either the direct or
indirect mode to print the line number being executed when the
program is RUN. The line numbers are displayed within square
brackets. The TRON function continues until a TROFF statement
or a NEW command is executed.
CLEAR E<string space>[,<highest address>]]
Sets all numeric variables to zero, all string variables to
null, and closes all open files; and optionally sets the end of
memory.
The <string space> parameter sets the memory size allocated for
string variables, with the default being 200 bytes. The
<highest address> parameter sets the highest memory address to
be used by MSX-BASIC.
DATA <list of constants>
Used to set the constants to be used by the program's READ
statements.
DATA statements are not executable and they may be placed
anywhere in a program. If a DATA statement is used to define
more than one constant, the constants must be delimited by
commas. The maximum number of constants that may be placed on
a logical line is limited only by the size of the logical line.
READ statements replace the constants for the variables used by
the program in the sequence listed in the DATA statement(s).
The <list of constants> may contain numeric constants in any
format: fixed point, floating point, or integer. Numeric
expressions are not allowed in DATA statements. String
constants may also be used in DATA statements. If the string
contains commas, colons, or significant leading or trailing
spaces, the string must be embedded in quotation marks.
The variable type required (numeric or string) required by a
READ statement must match the type specified in its DATA
statement. The RESTORE statement may be used to set the data to
be read from a specific line. If the RESTORE statement is not
used, the data is read from the program's first DATA statement.
Dim Clist of subscripted variables>
Specifies the maximum size of array variables.
If no DIM statement is specified, the maximum size allocated in
memory for the array is 10. If a subscript greater than the
maximum size is used, a 'Subscript out of range' error occurs.
The subscripts always begin at 0.
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MSX BASIC REFERENCE GUIDE
DEFINT <range(s) of letters>
DEFSNG <range(s) of letters>
DEFDBL <range(s) of letters>
DEFSTR <range(s) of letters>
Declares the variable type to be integer, single-precision,
double-precision, or string.
The DEFINT/SNG/DBL/STR statements declare that variable names
beginning with the letter(s) specified will always be
that type of variable. An exception to this rule is when a
variable type declaration character is used for a variable.
Section 2.1.5 lists the variable declaration characters.
DEF FN<name> [ ^parameter list>) ] =<f unction definition>
Defines and names a user-programmed function.
The <name> must be a legal variable name and is preceded by FN.
The <name> becomes the name of the defined function. The
<parameter list> comprises the variable names in the function
definition that are replaced when the function is called, and
they must be separated by commas. The <function definition> is
an expression performing the function, and is limited to to one
line. Variable names appearing in the expression serve only to
define the function; they do not affect program variables
having the same name. The <parameter list> may have a variable
name used, and if so, the value of the variable is supplied
when the function is called, otherwise, the current value of
the variable is used.
The variables in the parameter list represent, on a one-to-one
basis, the argument variables or values that will be given in
the function call.
If the function specifies a variable type, the expression's
value takes on that type befor being returned to the calling
statement. If the types specified in the function name and its
argument do not match, a 'lype mismatch' error occurs.
The DEFFN statement must be executed before the defined
function is used, if not, an 'Undefined user function' error
occurs. Note that DEFFN cannot be used in the direct mode.
DEFUSR[<digit>]=<integer expression>
Specifies the entry point of a machine language subroutine.
The <digit> may be any digit from 0 to 9, and corresponds to
the number of the USR routine whose address is being specified.
If <digit> is omitted, DEFUSRO is assumed. The value of
Cinteger expression> is the entry point of the USR routine.
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USX BASIC REFERENCE GUIDE
DEFUSR statements may be reused as many times as necessary
within a program to redefine the entry points of subroutines.
ERASE Clist of array variables>
Eliminates arrays from a program.
Arrays may be reDlMensioned after they are ERASEd, or the
previously allocated array space in memory may be used for
other purposes. If an attempt is made to reDIMension an array
without a prior ERASE, a ’Redimensioned array' error occurs.
END
Terminates program execution, closes all files and returns to
direct mode.
An END statement may be placed anywhere in a program to end its
execution. Unlike STOP, the END statement does not cause a
BREAK message to be displayed. An END statement located at the
end of a program is optional.
ERROR <integer expression>
Simulates the occurrence of an error or allows error codes to
be defined by the user.
The value of <integer expression> must be greater than 0 and
less than 255. If the value of Cinteger expression> equals an
error code already in use by BASIC, the ERROR statement will
simulate the occurrence of that error, and the corresponding
error message will be printed.
To define an error code, use a value that is greater than that
used by BASIC. Section 2.1.17 lists the error codes and
messages. Use the highest available codes to maintain
compatibility in case more error codes are added to later
versions of BASIC. The new user-defined error code may then be
handled in an error trap routine. One such example follows.
10 ON ERROR GOTO 1000
120 IF A$="Y" THEN ERROR 250
1000 IF ERR=250 THEN PRINT "Sure?"
If an ERROR statement specifyinge a code for which no error
message is defined or an ERROR statement having no error trap
routine is executed, MSX-BASIC will respond with an
’Unprintable error', and execution will be terminated.
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MSX BASIC REFERENCE GUIDE
FOR <variable>=x TO y [STEP zl
• •
NEXT [<variable>][,<variable>...]
Allows a series of instructions to be performed in a loop a
given number of times.
The <variable> is used as a counter for the FOR...NEXT loop.
It may be integer, single-precision, or double-precision, where
x, y, and z are numeric expressions. The first numeric
expression (x) is the initial value of the counter. The
second numeric expression (y) is the final value of the
counter. The program lines following the FOR statement are
executed until the NEXT statement is encountered. Then the
counter is incremented by the value of STEP. The value of
the counter is then compared with the final value (y), and if
it is not greater, execution is branched back to the statement
immediately following the FOR statement and the statements
within the loop are repeated. If the counter is exceeded,
execution continues with the statement following the NEXT
statement. If STEP is not specified, the default is one.
If STEP is negative, the final value of the counter must be
less than the initial value. The counter is decremented each
time through the loop, and the loop is executed until the
counter is less than the final value.
The loop is executed at least once if the initial value of the
loop times the sign of the step exceeds the final value times
the sign of the step.
FOR...NEXT loops may be nested, that is, a FOR...NEXT loop may
be placed within another FOR...NEXT loop. When loops are
nested, each loop must have a different variable name for its
counter. The NEXT statement for the inside loop must appear
before the NEXT for the outside loop. If nested loops share
the same end point, a single NEXT statement may be used for all
of them. The depth of nesting of FOR...NEXT loops is limited
only by the available memory.
The variable(s) in the NEXT statement may be omitted, in which
case the NEXT statement will match the most recent FOR
statement. If a NEXT statement is encountered before its
corresponding FOR statement, a 'NEXT without FOR' error message
is issued and execution is terminated.
GOSUB <line number>
RETURN [<1ine number>]
Branches to the subroutine beginning at <line number> and
returns from a subroutine.
The <line number> is the first line of the subroutine. A
subroutine may be called any number of times in a program, and
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MSX BASIC REFERENCE GUIDE
a subroutine may be called from within another subroutine.
Nesting of subroutines is limited only by the available memory.
RETURN statements in subroutines cause BASIC to branch back to
the statement following the most recent GOSUB statement. A
subroutine may contain more than one RETURN statement if it is
required by the program logic. Subroutines may be placed
anywhere in the program, but should be readily distinguishable
from the main program for greater understandability. To
prevent accidental entry into a subroutine, it may be preceded
by a STOP, END, or GOTO statement that directs program control
around the subroutine. Otherwise, a 'RETURN without GOSUB'
error will occur and execution terminates.
GOTO <line number>
Branches unconditionally out of the normal program sequence to
a specified <line number>.
If <line number> is an executable statement, that statement and
those following are executed. If it is a nonexecutable
statement, execution proceeds at the first executable statement
encountered after Cline number>.
IF <expression> THEN Cstatement(s)I Cline number>
[ELSE Cstatement(s) I Cline number>]
IF Cexpression> GOTO Cline number>
[ELSE Cstatement(s)I Cline number>]
Changes the program flow based on the result returned by an
expression.
If the result of Cexpression> is not zero, the THEN or GOTO
clause is executed. THEN may be followed by either a line
number for branching or one or more statements to be executed.
GOTO is always followed by a line number. If the result of
Cexpression> is zero, the THEN or GOTO clause is ignored and
the ELSE clause, if present, is executed. Execution continues
with the next executable statement.
Exampl e:
A=1:B=2 -> A=B is zero (FALSE).
A=2:b=2 -> A=B is not zero (TRUE).
IF_THEN...ELSE statements may be nested. Nesting is limited
only by the length of the line. If the statement does not
contain the same number of ELSE and THEN clauses, each ELSE is
matched with the closest unmatched THEN. For example, the
following statement will not print "AOC" when AOB.
IF A=B THEN IF B=C THEN PRINT "A=C"
ELSE PRINT "AOC"
The statement will print "AOC" when A=B and BOC.
If an IF...THEN statement is followed by a line number in the
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MSX BASIC REFERENCE GUIDE
direct mode, an ’Undefined line* error results unless a
statement with the specified line number had previously been
entered in the indirect mode.
INPUT ["<prompt string>"?]<1ist of variables>
Allows input from the keyboard during program execution.
When an INPUT statement is encountered, program execution
pauses and a question mark is printed to indicate that the
program is waiting for data. If a "<prompt string>" is
included, the string is printed before the question mark. The
required data is entered by the keyboard.
The data that is entered is assigned to the variable(s) given
in <variable list>. The number of data items supplied must be
the same as the number of variables in the list. The data
must be separated by commas.
The variables named in the <list of variables> may be numeric
or string variables (including subscripted variables). The
entered data type must agree with the type specified by the
variable name. Strings entered in response INPUT statements do
not need to be embedded in quotation marks.
If the wrong variable type is input (a string variable instead
of a numeric variable, etc.), a "PRedo from start” message is
displayed. No value is assigned until an acceptable response
is given. An example of this follows.
list
10 INPUT "A and B";A,B
20 PRINT A+B
Ok
run
A and B? 10,00
PRedo from start
A and B? 10,20
30
Ok
If the response to the INPUT statement has too many items, an
"PExtra ignored" message is displayed, and the next statement
is executed. One such example follows.
list
10 INPUT "A and B”;A,B
20 PRINT A+B
Ok
run
A and B? 10,20,30
PExtra ignored
30
Ok
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MSX BASIC REFERENCE GUIDE
Responding to an INPUT statement with too few items causes two
question marks to be printed and a wait for the next data item.
Example:
list
10 INPUT "A and B";A,B
20 PRINT A+B
Ok
run
A and B? 10 (The 10 was typed in by the user)
?? 20 (The 20 was typed in by the user)
30
Ok
The program can be suspended at the INPUT statement by typing
Control-C or by holding down the "CTRL” key and pressing
"STOP". MSX-BASIC will return to the direct mode and respond
with "Ok". To resume execution, type CONT.
LINE INPUT ["<prompt string>";]<string variable>
Inputs an entire line (up to 254 characters) to a string
variable, without the use of delimiters.
The <prompt string> is displayed on the console before input is
accepted. No question mark is printed unless it is a part of
the <prompt string>. All input typed to the console before a
carriage return is assigned to <string variable>.
The program can be suspended at the LINE INPUT statement by
typing Control-C or by holding down the "CTRL" key and pressing
"STOP". MSX-BASIC will return to the direct mode and respond
with "Ok". To resume execution, type CONT.
[LET] <variable>=<expression>
Assigns the value of an expression to a variable.
Note that the word LET is optional.
LPRINT [<list of expressions>]
LPRINT USING <string expressions<1ist of expressions>
Prints data on the line printer. (Refer to the PRINT and PRINT
USING statements below for details.)
MID?(<string exp. 1>),n[,m])=<string exp.2 >
Replaces a portion of one string with another string.
The characters in <string exp.l>, beginning at position n, are
replaced by the characters in <string exp.2>. The optional m
refers to the number of characters from <string exp.2> that
will be used in the replacement. If m is omitted or included,
the characters replaced does not go beyond the original length
of <string exp.l>.
ON ERROR GOTO <line number>
Enables error trapping and specifies the first line of the
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MSX BASIC REFERENCE GUIDE
error handling subroutine.
Once error trapping has been enabled, all errors detected,
including direct mode errors (e.g., Syntax errors), will cause
a jump to the specified error handling subroutine. If <line
number> does not exist, an 'Undefined line number' error
occurs. To disable error trapping, execute an ON ERROR GOTO 0.
Subsequent errors will then display error messages and halt
execution. An ON ERROR GOTO 0 statement appearing in an error
trapping subroutine will cause BASIC to stop and display the
error message for the error that caused the trap. It is
recommended that all error trapping subroutines execute an
ON ERROR GOTO 0 if an error is encountered for which there is
no recovery action.
If an error occurs during execution of an error handling
subroutine, the BASIC error message is printed and execution
terminates. Error trapping does not occur within the error
handling subroutine.
ON <expression> GOTO Clist of line numbers>
ON <expression> GOSUB <1ist of line numbers>
Branches to one of several specified line numbers, depending
on the value returned when an expression is evaluated. The
value of <expression> determines which line number in the list
will be used for branching. For example, if the value is
three, the third line number in the list will be the
destination of the branch. If the value is not an integer,
the fractional portion is discarded.)
In the ON...GOSUB statement, each line number in the list must
be the first line number of a subroutine.
If the value of <expression> is either zero or is greater than
the number of items in the list (and <= 255), MSX-BASIC
continues with the next executable statement. if the value of
<expression> is either negative or is greater than 255, an
'Illegal function call' error occurs.
POKE Cmemory address>,<integer expression>
Writes a (decimal) byte to a (decimal) memory location.
The <memory address> is the address of the memory location to
be written to (POKEd). The <integer expression> is the data
(byte) to be POKEd. It must be in the range 0 to 255. The
Cmemory address> must be in the range -32768 to 65535. If this
value is negative, the address is computed by subtraction from
65536. For example, a -1 is the same as 65535 (65536-1=65535).
Otherwise, art 'Overflow' error occurs.
PRINT [<list of expressions>]
Displays data to the console.
If the Clist of expressions> is omitted, a blank line is
printed. If the Clist of expressions> is included, the values
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MSX BASIC REFERENCE GUIDE
of the expressions are displayed on the console. An expression
in the list may be a numeric and/or a string expression.
Strings must be enclosed in quotation marks.
The position of each displayed item is determined by the
punctuation used to separate the items in the list. MSX-BASIC
divides the line into print zones of 14 spaces each. In the
<list of expressions>, a comma causes the next value to be
displayed at the beginning of the next zone. A semicolon
causes the next value to be displayed immediately after the
last value. One or more spaces between the expressions are
treated as semicolons.
If a comma or a semicolon terminates the Clist of expressions>,
the next PRINT statement begins printing on the same line,
spacing accordingly. If the <list of expressions> terminates
without a comma or a semicolon, a carriage return is printed at
the end of the line. If the printed line is longer than the
console width, MSX-BASIC goes to the next physical line and
continues printing.
A displayed number is always followed by a space. Positive
numbers are preceded by a space. Negative numbers are preceded
by a minus sign.
A question mark may be used instead of the word PRINT.
PRINT USING <string expression>;<1ist of expressions>
Displays strings or numerics using a specified format.
The <list of expressions> is comprised of the string
expressions or numeric expressions that are to be printed,
separated by semicolons. The <string expression> is a string
literal (or variable) comprising special formatting characters.
These formatting characters (see below) determine the field and
the format of the printed strings or numbers.
When PRINT USING is used to print strings, one of the following
three formatting characters may be used to format the string
field:
*t | n
Specifies that only the first character in the given string is
to be printed.
Example:
A$="Japan"
Ok
PRINT USING "I";A$
J
Ok
"& n spaces &" (Japanese. Refer to 5.4 for other versions.)
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MSX BASIC REFERENCE GUIDE
Specifies that 2+n characters from the string are to be printed.
If the 'S' signs are typed with no spaces, two characters will
be printed; with one space three characters will be printed,
and so on. If the string is longer than the field, the extra
characters are ignored. If the field is longer than the string,
the string will be left-justified in the field and padded with
spaces on the right.
Example:
A$="japan"
Ok
PRINT USING "& &";AS
Japa
Ok
n @ n (Japanese. Refer to 5.4 for other versions.)
Specifies that the whole character in the given string is to
be printed.
Example:
A$="Japan"
Ok
PRINT USING "I love @ very much.";A$
I love Japan very much.
Ok
When PRINT USING is used to print numbers,the following special
characters may be used to format the numeric field:
A number sign is used to represent each digit position. The
digit positions are always filled. If the number to be printed
has fewer digits than positions specified, the number will be
right-justified (preceded by spaces) in the field.
A decimal point may be inserted at any position in the field.
If the format string specifies that a digit is to precede the
decimal point, the digit will always be printed (as 0 if
necessary). Numbers are rounded as necessary.
Example:
PRINT USING "###.##";10.2,2,3.456,.24
10.20 2.00 3.46 0.24
Ok
A plus sign at the beginning or end of the format string will
cause the sign of the number (plus or minus) to be printed
before or after the number.
Example:
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USX BASIC REFERENCE GUIDE
PRINT USING "+###.##";1.25,-1.25
+1.25 -1.25
Ok
PRINT USING "###.##+";1.25,-1.25
1.25+ 1.25-
Ok
« _n
A minus sign at the end of the format field will cause negative
numbers to be printed with a trailing minus sign.
Example:
PRINT USING "###.##-";1.25,-1.25
1.25 1.25-
Ok
»**"
A double asterisk at the beginning of the format string causes
leading spaces in the numeric field to be filled with asterisks.
The ** also specifies positions for two or more digits.
Example:
PRINT USING ”**#.##";1.25,-1.25
**1.25*-1.25
Ok
"¥¥" (Japanese. Refer to 5.4 for other versions.)
A double yen sign causes a yen sign to be printed to the
immediate left of the formatted number. The ¥¥ specifies two
more digit positions, one of which is the yen sign. The
exponential format cannot be used with ¥¥. Negative numbers
cannot be used unless the minus sign trails to the right.
Example:
PRINT USING ”¥¥###.##";12.35,-12.35
¥12.35 -¥12.35
Ok
PRINT USING "¥¥###.##-"?12.35,-12.35
¥12.35 ¥12.35-
Ok
"**¥” (Japanase. Refer to 5.4 for other versions.)
The **¥ at the beginning of a format string combines the
effects of the above two symbols. Leading spaces will be
filled with asterisks and a yen sign will be printed before the
number. **¥ specifies three more digit positions, one of which
is the yen sign.
Example:
PRINT USING "**¥#.##";12.35
*¥12.35
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MSX BASIC REFERENCE GUIDE
Ok
If ff
t
A comma that is to the left of the decimal point in a
formatting string causes a comma to be printed to the left of
every third digit to the left of the decimal point. A comma
that is at the end of the format string is printed as part of
the string. A comma specifies another digit position. The
comma has no effect if used with the exponential format.
Example;
PRINT USING "####,.##"?1234.5
1,234.50
Ok
PRINT USING "####.##,";1234.5
1234.50,
Ok
II *
~ n
Four carats may be placed after the digit position characters
to specify exponential format. The four carats allow space for
E+xx to be printed. Any decimal point position may be
specified. The significant digits are left-justified, and the
exponent is adjusted. Unless a leading + or trailing + or - is
specified, one digit position will be used to the left of the
decimal point to print a space or minus sign.
Example;
PRINT USING "##.##--;234.56
2.35E+02
Ok
PRINT USING "#.##-;-12.34
1.23E+01-
Ok
PRINT USING "+#.##-";12.3 4,-12.34
+1.23 E+01-1.23 E+01
Ok
If the number to be printed is larger than the specified
numeric field, a percent sign is printed in front of the number.
Also, if rounding causes the number to exceed the field, a
percent sign will be printed in front of the rounded number.
Example:
PRINT USING "##.##";123.45
%123.45
Ok
PRINT USING 999
% 1.00
Ok
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MSX BASIC REFERENCE GUIDE
If the number of digits specified exceed 24, an 'Illegal
function call' error will result.
READ <list of variables>
Reads values from a DATA statement and assigns them to
variables.
A READ statement must always be used in conjunction with a DATA
statement. READ statements assign variables to DATA statement
values on a one-to-one basis. READ statement variables may be
numeric or string, and the values read must agree with the
variable types specified. If they do not agree, a 'Syntax
error' will result.
A single READ statement may access one or more DATA statements
(they will be accessed in order), or several READ statements
may access the same DATA statement. If the number of variables
in <1ist of variables> exceeds the number of elements in the
DATA statement(s), an 'Out of DATA' error will result. If the
number of variables specified is fewer than the number of
elements in the DATA statement(s), subsequent READ statements
will begin reading data at the first unread element. If there
are no subsequent READ statements, the extra data is ignored.
To reread DATA statements from the start, use the RESTORE
statement.
REM <remark>
Allows explanatory remarks to be inserted in a program.
REM statements are not executed but are output exactly as
entered when the program is listed.
REM statements may be branched to (from a GOTO or GOSUB
statement), and execution will continue with the first
executable statement after the REM statement.
Remarks may be added to the end of a line by preceding the
remark with a single quotation mark instead of :REM.
Do not use the above in a DATA statement as it would be
considered legal data.
RESTORE [<line number>]
Allows DATA statements to be reread from a specified line.
After a RESTORE statement is executed, the next READ statement
accesses the first item in the first DATA statement in the
program. If <1ine number> is specified, the next READ statement
accesses the first item in the specified DATA statement. If
a nonexistent line number is specified, an 'Undefined Line
number' error will result.
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MSX BASIC REFERENCE GUIDE
RESUME
RESUME 0
RESUME NEXT
RESUME <line number>
Continues program execution after an error recovery procedure
has been performed.
Any one of the four formats shown below may be used, depending
upon where execution is to resume:
RESUME or RESUME 0
Execution resumes at the statement which caused the error.
RESUME NEXT
Execution resumes at the statement immediately following the
one which caused the error.
RESUME <1 ine number>
Execution resumes at Cline number>
A RESUME statement that is not in an error trap subroutine
causes a 'RESUME without' error.
STOP
Terminates program execution and returns to command level.
A STOP statement may be used anywhere in a program to terminate
execution. When a STOP statement is encountered, the following
message is printed:
Break in nnnn (nnnn is a line number)
Unlike the END statement, the STOP statement does not close
files.
Execution is resumed by issuing a CONT command.
SWAP <variable>,<variable>
Exchanges the values of two variables.
Any type of variable may be SWAPped (integer, single-precision,
double-precision, string), but the two variables must be of
the same type, or a 'Type mismatch' error results.
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MSX BASIC REFERENCE GUIDE
2.1.12 Functions except those doing I/O
ABS(X)
Returns the absolute value of the expression X.
ASC(X?)
Returns a numerical value that is the ASCII code of the first
character of the string X?. If x? is null, a 'Illegal function
call' error is returned.
ATN(X)
Returns the arctangent of X in radians. Result is in the range
“pi/2 to pi/2. The expression X may be any numeric type, but
the evaluation of ATN is always performed in double precision.
BIN?(n)
Returns a string which represents the binary value of the
decimal argument. The numeric expression, n, must be between
-32768 and 65535. If n is negative, the two's complement is
used. That is, BIN$(-n) is the same as BIN?(65536-n).
CDBL(X)
Converts X to a double precision number.
CHR? (I)
Returns a string whose one element is the ASCII code for I.
CHR? is commonly used to send a special character to the
console.
CINT(X)
Converts X to an integer number by truncating the fractional
portion. If X is not between -32768 and 32767, an 'Overflow'
error occurs.
COS(X)
Returns the cosine of X in radians. COS(X) is calculated to
double precision.
CSNG(X)
Converts X to a single precision number.
CSRLIN
Returns the vertical coordinate of the cursor.
ERL/ERR
The ERR and ERL variables are usually used in IF-THEN
statements to direct program flow in the error trap routine.
When an error handling subroutine is entered, the variable ERR
contains the error code for error,and the variable ERL contains
the line number of the line in which the error was detected.
If the statement that caused the error was a direct mode
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MSX BASIC REFERENCE GUIDE
statement, ERL will contain 65535. To test if an error occurred
in a direct statement, use the following statement.
IF 6553 5=ERL THEN .....
Otherwise, use the following statements.
IF ERL=<line number> THEN ....
IF ERR=<error code> THEN....
Because ERL and ERR are reserved variables, neither may appear
to the left of the equals sign in a LET (assignment) statement.
EXP(X)
Returns e to the power of X. X must be <=145.06286085862. If
EXP overflows, the 'Overflow' error message is printed.
fix( x)
Returns the integer part of X (fraction truncated). FIX(X) is
equivalent to SGN(X) *INT(ABS(X) ) . The major difference between
FIX and INT is that FIX does not return the next lower number
for negative X.
FRE(O)
FRE ( " ")
Arguments to FRE are dummy arguments. FRE returns the number
of bytes in memory not being used by BASIC.
FRE(0) returns the number of bytes in memory which can be used
for BASIC programs, text files, and machine language program
files. FRE(" ") returns the number of bytes in memory for
string space.
HEX$(X)
Returns a string which represents the hexadecimal value of the
decimal argument. The numeric expression, n, must be between
-32768 and 65535. If n is negative, the two's complement form
is used. That is, HEX$(-n)is the same as HEX$(65536-n).
INKEY$
Returns either a one-character string containing a character
read from the keyboard or a null string if no key is pressed.
No characters will be echoed and all characters are passed
through to the program, except for Control-STOP, which
terminates the program.
INPUT? (X)
Returns a string of X characters, read from the keyboard. No
character will be echoed and all characters are passed through,
except for Control-STOP, which terminates the program.
INSTR([I,]X$,Y$)
Searches for the first occurrence of string Y$ in X$ and
returns the position at which the match is found. the optional
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USX BASIC REFERENCE GUIDE
offset I sets the position for starting the search. I must be
in the range 0 to 255. If I>LEN(X$) or if X$ is null or if Y$
cannot be found or if X$ and Y$ are null, INSTR returns 0. If
only Y$ is null, INSTR returns I or 1. X$ and Y$ may be
string variables, string expressions, or string literals.
INT(X)
Returns the largest integer <=X.
LEFT $ (X $, I)
Returns a string comprising the leftmost I characters of X$.
I must be in the range 0 to 255. If I is greater than LEN(X$),
the entire string (XS) is returned. If 1=0, a null string
(length zero) is returned.
LEN(X $)
Returns the number of characters in X$. Nonprinting characters
and blanks are counted.
LOG (X)
Returns the natural logarithm of X, X being greater than zero.
LPOS(X)
Returns the current position of the line printer print head
within the line printer buffer, not necessarily giving the
physical position of the print head. X is a dummy argument.
MID$(X$,II,j])
Returns a string of length J characters from X$ beginning with
the Ith character. I and J must be in the range 1 to 255. If
J is omitted or if there are fewer than J characters to the
right of the Ith character, all rightmost characters beginning
with the Ith character are returned. If I>LEN(X$), MID$
returns a null string.
0CT$ (n)
Returns a string which represents the octal value of the
decimal argument.
The numeric expression, n, must be between -32768 and 65535. If
n is negative, the two’s complement form is used, for example,
OCT $(-n) is the same as OCT$(65536-n).
PEEK (I)
Returns the byte (decimal integer in the range 0 to 255) read
from memory location I. I must be in the range -32768 to 65535.
PEEK is the complementary function to the POKE statement.
POS(I)
Returns the current cursor position. The leftmost position is
0. I is a dummy argument.
RIGHT? (X $, I)
Returns the rightmost I characters of string X$. If I=LEN(X$),
return X?. If 1-0, a null string (length zero) is returned.
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MSX BASIC REFERENCE GUIDE
RND(X)
Returns a random number between 0 and 1. The same sequence of
random number is generated each time the program is RUN. If
X<0, the random generator is reseeded for any given X. X=0
repeats the last number generated. X>0 generates the next
random number in the sequence.
SGN(X)
Returns 1 (for X>0), 0 (for X=0), -1 (for X<0) .
SIN(X)
Returns the sine of X in radians. SIN(X) is calculated to
double-precision.
SPACE$(X)
Returns the string of spaces of length X. The expression X
discards the fractional portion and must be range 0 to 255.
SPC(I)
Prints I blanks on the screen. SPC may only be used with PRINT
and LPRINT statements. I must be in the range 0 to 255.
SQR(X)
Returns the square root of X. X must be >=0.
STR$(X)
Returns a string representation of the value of X.
STRING $(I,J)
STRING $ (I, X$)
Returns a string of length I whose characters all have ASCII
code J or the first character of the string X$.
TAB(I)
Spaces to position I on the console. If the current print
position is already beyond space I, TAB does nothing. Space
0 is the leftmost position, and the rightmost position is the
width minus one. I must be in the range 0 to 255. TAB may only
be used with PRINT and LPRINT statements.
TAN(X)
Returns the tangent of X in radians. TAN(X) is calculated to
double precision. If TAN overflows, an 'Overflow' error will
occur.
USRl<digit>](X)
Calls the user's assembly language subroutine with the argument
X. <digit> is in the range 0 to 9 and corresponds to the digit
supplied with the DEFUSR statement for that routine. If <digit>
is omitted, USRO is assumed.
VAL(X $)
Returns the numerical value of the string X$. The VAL function
also strips leading blanks, tabs, and linefeeds from the
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USX BASIC REFERENCE GUIDE
argument string. The following is an example.
PRINT VAL(" -7")
-7
Ok
VARPTR(<variable name>)
VARPTR(#<file number>)
Returns the address of the first byte of data identified with
<variable name>. A value must be assigned to <variable name>
prior to execution of VARPTR. Otherwise, an 'Illegal function
call' error results. Any type of variable name may be used
(numeric, string, array), and the address returned will be
an integer in the range -32768 to 32767. If a negative address
is returned, add it to 65536 to obtain the actual address.
VARPTR is usually used to obtain the address of a variable or
array so it may be passed to a machine language subroutine.
A function call of the form VARPTR(A(0)) is usually specified
when passing an array, so that the lowest-address element of
the array is returned.
All simple variables should be assigned before calling VARPTR
for an array because the address of the arrays change whenever
a flaw simple variable is assigned. If #<file number> is
specified, VARPTR returns the starting address of the file
control block.
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MSX BASIC REFERENCE GUIDE
- Expanded Statements and Functions for MSX -
2.1.13 Device Specific Statements
SCREEN [<mode>l t,<sprite size>H,<key click switch>]
[,<cassette baud rate>][,<printer option>]
Assigns the screen mode, sprite size, key click, cassette baud
rate, and printer option.
<mode> should be set to 0 to select 40x24 text mode, 1 to
select 32x24 text mode, 2 to select high resolution mode, 3
to select multi-color (low-resolution mode).
0: 40x24, text mode
1: 32x24, text mode
2: high-resolution mode
3: multi-color mode
<sprite size> determines the size of sprite. Should be set to
0 to select 8x8 unmagnified sprites, 1 to select 8x8 magnified
sprites, 2 to select 16x16 unmagnified sprites, 3 to select
16x16 magnified sprites. NOTE: If <sprite size> is specified,
the contents of SPRITE? will be cleared.
0: 8x8, unmagnified
1: 8x8, magnified
2: 16x16, unmagnified
3: 16x16, magnified
<key click switch> determines whether to enable or disable the
key click. Should be set to 0 to disable it.
0: disable key click
non-zero: enable key click
Note that in text mode, all graphics statements except PUT
SPRITE' qenerate an 'Illegal function call' error. Note also
that the mode is forced to text mode when an 1 INPUT statement
is encountered or BASIC returns to command level.
<cassette baud rate> determines the default baud rate for
succeeding write operations, 1 for 1200 baud, and 2 for 2400
baud. The baud rate can also be determined using CSAVE command
with baud rate option.
Note that when reading cassette, the baud rate is automatically
determined, so that users do not need to know the baud rate
the cassette is written. <printer option> determines if the
printer in operation is 'MSX printer' (which has 'graphics
symbol' and 'Hiragana' capability) or not. Should be non 0 if
the printer does not have such capability. In this case.
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HSX BASIC REFERENCE GUIDE
graphics symbols are converted to spaces, and Hiragana
are converted to Katakana in the Japanese version.
WIDTH <width of screen in text mode>
Sets the width of the display during text mode. Valid values
are 1 to 40 in 40x24 text mode, and 1 to 32 in 32x24 text mode.
CLS
Clears the screen. Valid in all screen modes.
LOCATE [<x>][,<y>][,<cursor display switch>]
Locates character the position for PRINT. <cursor display
switch> can be specified only in text mode.
0: Disable the cursor display
1: Enable the cursor display
COLOR Kforeground color >][, -(background color>] [ ,<border color>]
Defines the color, the default being 15,4,7 in the Japanese
version. Refer to 5.4 for other versions. The argument can be
in the range of 0 to 15. The color correspondences follow.
0 Transparent
1 Black
2 Medium green
3 Light green
4 Dark blue
5 Light blue
6 Dark red
7 Cyan
8 Medium red
9 Light red
10 Dark yellow
11 Light yellow
12 Dark green
13 Magenta
14 Gray
15 White
PUT SPRITE <sprite plane number>[,<coordinate specifier>]
[,<color>][,<pattern number>]
Sets up sprite attributes.
<sprite plane number> may range from 0 to 31.
<coordinates specifier> always ca come in one of two forms:
STEP { x offset, y offset) or
( absolute x, absolute y)
The first form is a point relative to the most recent point
referenced. The second, more common, form is directly refers
to a point without regard to the last point referenced.
The foilwing are some examples.
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MSX BASIC REFERENCE GUIDE
(10,10) absolute form
STEP (10,0) offset 10 in x and 0 in y
(0,0) origin
Note that when BASIC scans coordinate values it will allow them
to be beyond the edge of the screen, however values outside the
integer range (-32768 to 32767) will cause an overflow error.
And the values outside of the screen will be substituted with
the nearest possible value. For example, 0 for any negative
coordinate specification.
Note that (0,0) is always the upper left-hand corner. Although
numbering y at the top causes the bottom left corner to be
(0,191) in both high- and medium-resolution, this is standard.
The above description can be applied wherever graphic
coordinates are used.
The X coordinate <x> may range from -32 to 255. The Y
coordinate <y> may range from -32 to 191. If 208 (&HD0) is
given to <y>, all sprite planes behind disappears until a value
other than 208 is given to that plane. If 209 (&HD1) is
specified to <y>, that sprite disappears from the screen.
Refer to the VDP manual for further details.
When a field is omitted, the current value is used. At start
up, the color defaults to the current foreground color.
<pattern number> specifies the pattern of sprite, and must be
less than 256 when size of sprites if 0 or 1, and must be less
than 64 when the size of sprites is 2 or 3. <pattern number>
defaults to the <sprite plane number>. See also the SCREEN
statement and the SPRITES variable.
CIRCLE Coordinate specif ier>,<radius> [, <color>]
[,<start angle>][,<end angle>l[,<aspect ratio>]
Draws an ellipse with a center and radius as indicated by the
first of its arguments.
Coordinate specifier> specifies the coordinate of the center
of the circle on the screen. For details on Coordinate
specifier)*, see the description of the PUT SPRITE statement.
The <color> defaults to foreground color.
The <start angle> and <end angle> parameters are radian
arguments between 0 and 2*PI which allow you to specify where
drawing of the ellipse will begin and end. If the start or end
angle is negative, the ellipse will be connected to the center
point with a line, and the angles will be treated as if they
were positive. Note that this is different than adding 2*PI.
The <aspect ratio is for horizontal and vertical ratio of the
ellipse.
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MSX BASIC REFERENCE GUIDE
DRAW <string expression>
Draws figure according to the graphic macro language.
The graphic macro language commands are contained in the string
expression string. The string defines an object, drawn when
BASIC executes the DRAW statement. During execution, BASIC ex¬
amines the value of string and interprets single-letter com¬
mands from the contents of the string. These commands are des¬
cribed in detail below:
The following movement commands begin movement from the last
point referenced. After each command, last point referenced
is the last point the command draws.
u
n
Moves
up
D
n
Moves
down
L
n
Moves
left
R
n
Moves
right
E
n
Moves
diagonally
up and right
F
n
Moves
diagonally
down and right
G
n
Moves
diagonally
down and left
H
n
Moves
diagonally
up and left
The n in each of the preceding commands indicates the distance
to move. The number of points moved is n times the scaling
factor set by the S command.
M x,y Moves absolute or relative. If x has a plus
sign(+) or a minus sign(-) in front of it, it
is relative. Otherwise, it is absolute.
The aspect ratio of the screen is 1. Thus, 8 horizontal points
are equal to 8 vertical points.
The following two prefix commands may precede any of the above
mov em ent commands.
B Moves, but doesn't plot any points.
N Moves, but returns to the original position
when finished.
The following commands are also available:
A n Sets angle n. n may range from 0 to 3, where
0 is 0 degrees, 1 is 90, 2 is 180, and 3 is 270.
0
2
C n Sets color n, being between 0 and 15.
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MSX BASIC REFERENCE GUIDE
S n Sets the scale factor, n being betwen 0 and 255.
The scale factor is n/4. For example, if n = 1,
the scale factor is 1/4. The scale factor is
multiplied by the distance given with U,D, L,R, E,
F,G,and H; and relative M commands give the dis¬
tance moved. The default value is 0, meaning 'no
(i.e. , it is the same as S4) .
X<string variable>:
Executes substring. This allows you to execute
a second string from within a string.
Example A$="U80R80D80L80":DRAW "XA$;"
->Draws a square
In all of these commands, the n, x, or y argument can be a
constant like 123 or it can be 1 =<variable>; 1 where <variable>
is the name of a numeric variable. The semicolon (;) is
required if the variable is used this way, or in the X command.
Otherwise, a semicolon is optional between commands. Spaces
are ignored in string. For example, variables in a move com¬
mand in this way:
Xl=40:X2=5 0
DRAW "M+=xl;,-=X2"
The X command can be a very useful part of DRAW, because you
can define a part of an object separate from the entire object
and also can use X to draw a string of commands more than 255
characters long.
LINE [Ccoordinate specifier>]-Ccoordinate specifier>[,Ccolor>]
[ ,<B IBF>]
Draws a line connecting the two specified coordinate. For the
details on the Ccoordinate specifier>, see the description of
the PUT SPRITE statement.
If 'B 1 is specified, a rectangle is drawn. If 'BF' is speci¬
fied, the rectangle is filled.
PAINT Ccoordinate specifier>[,Cpaint color>][,Cborder color>]
Fills in a bordered figure with the specified fill color from
the Ccoordinate specifiers See the description on PUT SPRITE
for details of the Ccoordinate specifier>. The PAINT statement
does not allow Ccoordinate specifier> to be off the screen.
Note that PAINT must not have a border for high-resolution
graphics, border can be specified only in multicolor mode. In
high-resolution graphics mode, the paint color is regarded as
the border color.
PSETCcoordinate specifier^,Ccolor>]
PRESETCcoordinate specifier>[,Ccolor>]
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USX BASIC REFERENCE GUIDE
Sets/resets the specified coordinate. For details of the
<coordinate specifier>, see the description on PUT SPRITE.
The only difference between PSET and PRESET is that if no
<color> is given in PRESET statement, the background color is
selected. When a <color> argument is given, PRESET is
identical to PSET.
KEY <function key #>,<string expression>
Sets a string to specified function key. <function key #>
must be in the range 1 to 10. <string expression> must be
within 15 characters.
Example:
KEY 1,"PRINT TIME$"+CHR$ (13)
A$="Japan"
KEY 2,A$
KEY LIST
Lists the contents of all function keys.
Exampl e:
KEY LIST
color
auto
goto
list
run
color 15,7,7
cload"
cont
list .
run
Ok
"color" corresponds to key "fl", "auto" with "f2", "goto" with
"f3", and so on. Position in the list reflects the key
assignments. Note that control characters assigned to function
keys are converted to spaces.
KEY ON I OFF
Turns on/off function key display on 24th line of text screen.
ON KEY GOSUB <list of line numbers>
Sets up a line numbers for BASIC to trap to when the function
keys is pressed.
Example:
ON KEY GOSUB 100,200,,400,,500
When a trap occurs, an automatic KEY(n)STOP is executed so
receive traps can never take place. The RETURN from the trap
routine will automatically do a KEY(n)ON unless an explicit
KEY(n)OFF has been performed inside the trap routine.
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MSX BASIC REFERENCE GUIDE
Event trapping does not take place when BASIC is not executing
a program. When an error trap (resulting from an ON ERROR
statement) takes place this automatically disables all trapping
(including ERROR, STRIG, STOP, SPRITE, INTERVAL and KEY).
KEY (<function key #>) ON/OFF/STOP
Activates/deactivates trapping of the specified function key
in a BASIC program.
A KEY(n)ON statement must be executed to activate trapping of
function key. After a KEY(n)ON statement, if a line number is
specified in the ON KEY GOSUB statement then every time BASIC
starts a new statement it will check to see if the specified
key was pressed. If so, it will perform a GOSUB to the line
number specified in the ON KEY GOSUB statement.
If a KEY(n)OFF statement has been executed, no trapping takes
place and the event is ignored.
If a KEY(n)STOP statement has been executed, no trapping will
take place, but if the specified key is pressed, this is
remembered so trapping is done if KEY(n)ON is executed.
KEY(n)ON does not affect the function key assignments displayed
at the bottom of the console.
ON STRIG GOSUB <list of line numbers>
Sets up a line numbers for BASIC to trap to when the trigger
button is pressed.
Example:
ON STRIG GOSUB ,200,, 400
When the trap occurs an automatic STRIG(n)STOP is executed so
receive traps can never take place. The RETURN from the trap
routine will automatically do a STRIG(n)ON unless an explicit
STRIG(n)OFF has been performed inside the trap routine.
Event trapping does not take place when BASIC is not executing
a program. When an error trap (resulting from an ON ERROR
statement) takes place, all trapping (including ERROR, STRIG,
STOP, SPRITE, INTERVAL and KEY)is automatically disabled.
STRIG (<n>) ON/OFF/STOP
Activates or deactivates trapping of joystic trigger buttons in
BASIC programs.
<n> can be between 0 and 4. If <n> = 0, the space bar is used
for a trigger button. If <n> is either 1 or 3, the trigger of a
joystick 1 is used. When <n> is either 2 or 4, joystick 2 is
used.
A STRIG(n)ON statement must be executed to activate trapping
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MSX BASIC REFERENCE GUIDE
of the trigger button. After an STRIG(n)ON statement is execu¬
ted, if a line number is specified in the ON STRIG GOSUB state¬
ment, then every time BASIC starts a new statement, it will
check to see if the trigger button was pressed. If so, it will
perform a GOSUB to the line number specified in the ON STRIG
GOSUB statement.
If a STRIG(n)OFF statement has been executed, no trapping takes
place and the event is not remembered even if it does take
place.
If a STRIG(n)STOP statement has been executed, no trapping will
take place, but if the trigger button is pressed this is
remembered so an immediate trap will take place when STRIG(n)ON
is executed.
ON STOP GOSUB Cline number>
Sets up a line numbers for BASIC to trap to when the Control-
STOP key is pressed.
When the trap occurs, the STOP STOP statement is executed so
receive traps can never take place. The RETURN from the trap
routine will automatically do a STOP ON unless an explicit STOP
OFF has been performed inside the trap routine.
Event trapping does not take place when BASIC is not executing
a program. When an error trap (resulting from an ON ERROR
statement) takes place, all trapping (including ERROR, STOP,
STRIG, SPRITE, INTERVAL and KEY) are automatically disabled.
Use caution when using this statement. For example, the follo¬
wing program cannot be aborted, and the only way out is to
reset the systeml
10 ON STOP GOSUB 40
20 STOP ON
30 GOTO 30
40 RETURN
STOP ON/OFF/STOP
Activates/deactivates trapping of control-STOP.
A STOP ON statement must be executed to activate trapping of
a control-STOP. After STOP ON statement, if a line number is
specified in the ON STOP GOSUB statement, then every time BASIC
starts a new statement, it will check to see if a control-STOP
was pressed. If so, it will perform a GOSUB to the line number
specified in the ON STOP GOSUB statement.
If a STOP OFF statement has been executed, no trapping takes
place and the event is not remembered even if it does take
place.
If a STOP STOP statement has been executed, no trapping will
take place. But if a Control-STOP is pressed,this is remembered.
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MSX BASIC REFERENCE GUIDE
so an immediate trap will take place when STOP ON is executed.
ON SPRITE GOSUB <line number>
Sets up a line number for BASIC to trap to when the sprites
coincide.
When the trap occurs an automatic SPRITE STOP is executed so
receive traps can never take place. The RETURN from the trap
routine will automatically do a SPRITE ON unless an explicit
SPRITE OFF has been performed inside the trap routine.
Event trapping does not take place when BASIC is not executing
a program. When an error trap (resulting from an ON ERROR
statement) takes place this automatically disables all trapping
(including ERROR, STRIG, STOP, SPRITE, INTERVAL and KEY).
SPRITE ON/OFF/STOP
Activates/deactivates trapping of sprite in a BASIC program.
A SPRITE ON statement must be executed to activate trapping of
sprite. After SPRITE ON statement, if a line number is
specified in the ON SPRITE GOSUB statement then every time
BASIC starts a new statement it will check to see if the
sprites coincide. If so, it will perform a GOSUB to the line
number specified in the ON SPRITE GOSUB statement.
If a SPRITE OFF statement has been executed, no trapping takes
place and the event is not remembered even if it does take
place.
If a SPRITE STOP statement has been executed, no trapping will
take place. But if the sprites coincide, this is remembered so
an immediate trap will take place when SPRITE ON is executed.
ON INTERVAL=<time interval> GOSUB <line number>
Sets up a line number for BASIC to trap to time interval.
Generates a timer interrupt every <time interval>/60 second.
When the trap occurs an automatic INTERVAL STOP is executed so
receive traps can never take place. The RETURN from the trap
routine will automatically do a INTERVAL ON unless an explicit
INTERVAL OFF has been performed inside the trap routine.
Event trapping does not take place when BASIC is not executing
a program. When an error trap (resulting from an ON ERROR
statement) takes place this automatically disables all traps
(including ERROR, STRIG, STOP, SPRITE, INTERVAL and KEY).
INTERVAL ON/OFF/STOP
Activates/deactivates trapping of time intervals.
A INTERVAL ON statement must be executed to activate trapping
of time interval. After INTERVAL ON statement, if a line
number is specified in the ON INTERVAL GOSUB statement, then
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MSX BASIC REFERENCE GUIDE
every time BASIC starts a new statement it will check the time
interval. if so, it will perform a GOSUB to the line number
specified in the ON INTERVAL GOSUB statement.
If a INTERVAL OFF statement has been executed, no trapping
takes place and the event is not remembered even if it does
take place.
If a INTERVAL STOP statement has been executed, no trapping
will take place. But if the timer interrupt occurs, this is
remembered so an immediate trap will take place when INTERVAL
ON is executed.
VPOKE <address of VRAM>,<value to be written>
Pokes a value to specified location of VRAM. <address of VRAM>
can be between 0 and 16383. <value to be written> should be a
byte value.
BEEP
Generates a beep sound, as for the output of CHR$(7).
MOTOR [<ONI0FF>]
Changes the status of cassette motor switch. When no argument
is given, flips the motor switch. Otherwise, enables/disables
motor of cassette.
SOUND <register of PSG>,<value to be written>
Writes value directly to the <register of PSG>.
PLAY <string exp for voice l>[,<string exp for voice 2>
[,<string exp for voice 3>]]
Plays music according to the music macro language.
PLAY implements a concept similar to DRAW by embedding a "music
macro language" into a character string. <string exp for voice
n> is a string expression consisting of single character music
commands. When a null string is specified, the voice channel
remains silent. The single character commands in PLAY are:
A to G with optional #,+,or -
Plays the indicated note in the current octave.
A number sign(#) or plus sign(+) afterwards
indicates a sharp, a minus sign(-) indicates
a flat. The #,+, or - is not allowed unless
it corresponds to a black key on a piano. For
example, B# is an invalid note.
0 n Octave. Sets the current octave for the
following notes. There are 8 octaves, numbered
1 to 8. Each octave goes from C to B. Octave
4 is the default octave.
N n Plays note n. n may range from 0 to 96. n=0
means rest. This is an alternative way of
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MSX BASIC REFERENCE GUIDE
L n
R n
T n
V n
M n
S n
selecting notes besides specifying the octave(0
n) and the note name (A-G). (The C of octave
4 is 36.)
Sets the length of the following notes. The
actual note length is 1/n. n may range from
1 to 64. The following table may help explain
this:
Length Equivalent
LI Whole note
L2 Half note
L3 One of a triplet of three
half notes (1/3 of a 4 beat
measure)
L4 Quarter note
L5 One of a quintuplet (1/5
of a measure)
L6 One of a quarter note triplet
L64 Sixty-forth note
The length may also follow the note when you
want to change the length only for the note.
For example,
default is 4
A16 is
•
equivalent
to L16A.
The
Pause (rest)
. n may
range from
1 to 64,
and
figures the
length
of the pause
in the
same
way as L(length). The default is 4.
(Dot or period) After a note, causes the note
to be played as a dotted note. That is, its
length is multiplied by 3/2. More than one
dot may appear after the note, l/(2~n) is added
per one dot. For example, "A..." will play
15/8 as long, etc. Dots may also appear after
the pause(P) to scale the pause length in the
same way.
Tempo. Sets the number of quarter notes in
a minute, n may range from 32 to 255. The
default is 120.
Volume. Sets the volume of output, n may range
from 0 to 15. The default is 8.
Modulation. Sets period of envelope. n may
range from 1 to 65535. The default is 255.
Shape. Sets shape of envelope. n may range
from 1 to 15. The default is 1. The pattern
set by this command are as follows:
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USX BASIC REFERENCE GUIDE
• WM
*• NAAAA
■■ \f-'
» A/wwm
13
14
/ -
AWV
X<variable>;
/Executes specified string.
In all of these commands, the n argument can be a constant like
s 2 <ra r - can b !L" ~ <var iable>f " where variable is the name of
a variable. The semicolon(;> is required when you use a
variable in this way, and when you use the X command.
erwise ' a semicolon is optional between commands. Note that
the values specified in the above commands will be reset to the
system default when a beep sound is generated*
MAXFILES=<expression>
Specifies the maximum number of files opened at a time.
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MSX BASIC REFERENCE GUIDE
<expression> can be in the range of 0 to 15. When l MAXFILES=0'
is executed, only SAVE and LOAD can be performed. The default
value assigned is 1.
OPEN "<device_descriptor>[<file name>]" [FOR <mode>]
AS [#3<file number>
Allocates a buffer for I/O and set the mode that will be used
with the buffer.
This statement opens a device for further processing.
Currently, the following devices are supported.
CAS: Cassette
CRT: CRT screen
GRP: Graphic screen
LPT: Line printer
Device descriptors can be added using the ROM cartridge. See
section 2.2.3 for further details.
<mode> is one of the following:
OUTPUT : Sequential output mode
INPUT : Sequential input mode
APPEND : Sequential append mode
<file number> is an integer expression whose value is between
one and the maximum number of files specified in a MAXFILES=
statement.
<file number> is the number that is associated with the file
for as long as it is OPEN and is used by other I/O statements
to refer to the file.
An OPEN must be executed before any I/O may be done to the file
using any of the following statements, or any statement or
function requiring a file number:
PRINT #, PRINT # USING
INPUT #, LINE INPUT #
INPUT?, GET, PUT
PRINT #<£ile number>,<exp>
PRINT #<file number>,USING <string expression^-<list of expression>
Writes data to the specified channel. Refer to the PRINT and
PRINT USING statements for details.
INPUT #<file number>,<variable list>
Reads data items from the specified channel and assigns them to
program variables.
The type of data in the file must match the type specified by
the <variable list>. Unlike the INPUT statement, no question
mark is printed with INPUT# statement.
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USX BASIC REFERENCE GUIDE
The data items in the file should appear just as they would if
data were being typed in response to an INPUT statement. With
numeric values, the leading spaces, carriage returns, and line
feeds are ignored. The first character encountered that is not
a space, carriage return, or line feed is assumed to be start
of a number. The number terminates on a space, carriage
return, line feed, or comma.
Also, if BASIC is scanning the data for a string item, leading
spaces, carriage returns, and line feeds are ignored. The first
character encountered that is not a space, carriage return, or
line feed is assumed to be the start of a string item. If this
first character is a double-quotation mark ("), the string item
will consist of all characters read between the first quotation
mark and the second. Thus, a quoted string may not contain a
quotation mark as a character.
If the first character of the string is not a quotation mark,
the string is an unquoted string, and will terminate on a
comma, carriage return, line feed, or after 255 characters
have been read. If end of file is reached when a numeric or
string item is being INPUT, the item is terminated.
LINE INPUT #<file number>,<string variable>
Reads an entire line (up to 254 characters), without delimiters,
from a sequential file to a string variable.
<file number> is the number which the file was OPENed.
<string variable> is the name of a string variable to which the
line will be assigned.
LINE INPUT# reads all characters in the sequential file up to
a carriage return. It then skips over the carriage return/line
feed sequence, and the next LINE INPUT# reads all characters
up to the next carriage return. (If a line feed/carriage return
sequence is encountered, it is preserved. That is, the line
feed/carriage return characters are returned as part of the
string.)
LINE INPUT# is especially useful if each line of a file has
been broken into fields, or if a BASIC program saved in ASCII
mode is being read as data by another program.
INPUTS(n,E#J<file number>)
Returns a string of n characters, read from the file. <file
number> is the number which the file was OPENed.
CLOSE [[#]<file number>[,<file number>]]
Closes the channel and releases the buffer associated with it.
If no <file number> is specified, all open channels are closed.
SAVE "<device descriptor>[<file name>]"
Saves a BASIC program file to the device. Control-Z is treated
as end-of-file.
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MSX BASIC REFERENCE GUIDE
LOAD "<device_descriptor>[<file name>]"
Loads a BASIC program file from the device.
LOAD closes all open files and deletes the current program from
memory. However, with the "R n option, all data files remain
OPEN and execute the loaded program.
If the <file name> is omitted, the next program, which should
be an ASCII file, encountered on the tape is loaded. Control-2
is treated as end-of-file.
MERGE "<device descriptor>Kfile name>]"
Merges the lines from an ASCII program file into the program
currently in memory.
If any lines in the file being merged have the same line number
as lines in the program in memory, the lines from the file will
replace the corresponding lines in memory.
After the MERGE command, the MERGEd program resides in memory,
and BASIC returns to command level.
If <file name> is omitted, the next program file, which should
be in ASCII format, encountered on cassette tape is MERGEd. A
Control-Z is treated as end-of-file character.
BSAVE "<device descriptor>[<file name>]",<top adrs>,<end adrs>
[,<execution adrs>]
Saves a memory image at the specified memory location to the
device. (Currently, only CAS: is supported.)
<top adrs> and <end adrs> are the top address and the end
address of the area to be saved.
If <execution adrs> is omitted, <top adrs> is regarded as
<execution adrs>.
Examples:
BSAVE "CASiTEST",&HA000,&HAFFF
BSAVE "CAS :GAME", &HE000 , &HE0FF, &HE020
BLOAD "<device_de script or > Kf ile name>]"[,R1I,<offset>]
Loads a machine language program from the specified device.
(Currently only CAS: is supported.)
If R option is specified, after the loading, program begins
execution automatically from the address which is specified at
BSAVE.
The loaded machine language program will be stored at the
memory location which is specified at BSAVE. If <offset> is
specified, all addresses which are specified at BSAVE are
offset by that value.
98
MSX BASIC REFERENCE GUIDE
If the <file name> is omitted, the next machine language
program file encountered is loaded.
CSAVE "<f ile name>"[,<baud rate>]
Saves a BASIC program in binary format on cassette tape.
BASIC saves the file in a compressed binary (tokenized) format.
ASCII files take up more space, but some types of access
require that files be in ASCII format. For example, a file
to be later MERGEd must be saved in ASCII format. Programs
saved in ASCII may be read as BASIC data files and text files.
Use the SAVE command instead for ASCII format.
<baud rate> is a parameter from 1 to 2, which determines the
default baud rate for every cassette write operations. 1 for
1200 baud, 2 for 2400 baud. The default baud rate can also be
set with SCREEN statement.
CLOAD [ n <file name>"]
Loads a BASIC program file from the cassette tape.
CLOAD closes all open files and deletes the current program
from memory. If the <file name) is omitted, the next program
file encountered on the tape is loaded. For all cassette read
operations, the baud rate is determined automatically.
CLOAD? ["<file name>"]
Checks if the program on cassette matches the one in memory.
CALL Cname of expanded statements Uargument list>)]
Invokes an expanded statement supplied by ROM cartridge. See
section 2.2.3 for further details. is an abbreviation for
'CALL', so the next 2 statements have the same meaning.
CALL TALK ("Yamashita","Hayashi","Suzuki GSX400FW")
_TALK(" Yamashita", "Hayashi", "Suzuki GSX400FW")
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MSX BASIC REFERENCE GUIDE
2.1.14 I/O Functions
POINTKX coordinated<Y coordinated
Returns the color of a specified pixel.
VPEEK Kaddress of VRAM>)
Returns a value of VRAM specified. <address of VRAM> can be
in the range of 0 to 16383.
STICK(<n>)
Returns the direction of a joystick. <n> can be in the range
of 0 to 2. If <n>=0, the cursor key is used as a joystick. If
<n> is either 1 or 2, the joystick connected to proper port
is used. When neutral, 0 is returned. Otherwise, the value
corresponding to direction is returned.
\i/
7 -o-3
/l\
5
STRIG (< n >)
Returns the status of a trigger button of a joystick. <n> can
be in the range of 0-4. If <n>=0, the space bar is used for
a trigger button. If <n> is either 1 or 3, the trigger of a
joystick 1 is used. When <n> is either 2 or 4, joystick 2.
0 is returned if the trigger is not being pressed, -1 is
returned otherwise.
PDL(<n>)
Returns the value of a paddle. <n> can be in the range of
1 to 12. If <n> is either 1, 3, 5, 7, 9 or 11, the paddle
connected to port 1 is used. When 2, 4, 6, 8, 10 or 12,
the paddle connected to port 2 is used.
PAD(<n>)
Returns various status of touch pad. <n> can be in the range
of 0 to 7.
When 0 to 3 is specified, the touch pad connected to joystick
port 1 is selected, if between 4 to 7, port 2 is selected.
When <n>=0 or 4, the status of touch pad is returned, -1 when
touched, 0 when released.
When <n>=l or 5, the X-coordinate is returned, when <n>=2 or
6, Y-coordinate is returned.
When <n>=3 or 7, the status of switch on the pad is returned.
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MSX BASIC REFERENCE GUIDE
-1 when being pushed, 0 otherwise.
Note that coordinates are valid only when PAD(O) (or PAD(4))
is evaluated. When PAD(O) is evaluated, PAD (5) and PAD (6) are
both affected, and when PAD(4), PAD(l) and PAD(2).
PLAY(<play channel>)
Returns the status of a music queue. <n> can be in the range
of 0-3. If <n>=0, all 3 status are ORed and returned. If <n>
is either 1,2 or 3, -1 is returned if the queue is still in
operation, i.e., still playing. 0 is returned otherwise. Note
that immediately after the PLAY statement is issued, the PLAY
function returns -1 regardless of the actual status of the
music queue.
EOF(<file number>)
Returns -1 (true) if the end of a sequential file has been
reached. Otherwise, returns 0. Use EOF to test for end-of-file
while INPUTing, to avoid 'Input past end' errors.
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MSX BASIC REFERENCE GUIDE
2.1.15 Special Variables
The following are special variables for MSX. When assigned, the
content is changed, when evaluated, the current value is returned.
TIME (type: unsigned integer)
The system internal timer. TIME is automatically incremented
by 1 everytime VDP generates interrupt (60 times per second),
thus, when an interrupt is disabled (for example, when
manipulating cassette), it retains the old value.
SPRITE $(<pattern number>) (type: string)
The sprite pattern.
<pattern number> must be less than 256 when size of sprites is
0 or 1, less than 64 when size of sprites is 2 or 3.
The length of this variable is fixed to 32 (bytes). So, if
a string that is shorter than 32 character is assigned, the
CHR$(0)s are added.
Example:
list
100 SCREEN 3,3
110 A$=CHR$ (1) +CHR$ (3) +CHR$(7) +CHR$ (&HF) +CHR$ (&H1F)
+CHR$(&H3F)+CHR$(&H7F)+CHR$(&HFF)
120 SPRITE $(1) =A$
13 0 SPRITE $(2) =A$+A$
140 SPRITES(3) =A$+A$+A$
150 SPRITE $(4) =A$+A$+A$+A$
160 PUT SPRITE 1,(20,20) ,15
170 PUT SPRITE 2,(60,20 ,15
180 PUT SPRITE 3,(100,20 ,15
190 PUT SPRITE 4,(140,20 ,15
200 GOTO 200
Ok
run
******************************************************************
* NOTE *
* The following two are system variables which can be evaluated *
* or assigned like other ordinary variables. Prepared for *
* advanced programmers only. If you do not understand their *
* usage fully, please do not use them. *
* *
******************************************************************
VDP(<n>) (type: unsigned byte)
If <n> is between 0 to 7, VDP(n) specifies the current value of
the VDP write-only register. If <n> is 8, it specifies the
status register of the VDP. VDP(8) is read only.
BASE(<n>) (type: integer)
Current base address for each table. The description of <n>
follows next.
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MSX BASIC REFERENCE GUIDE
0 - Base of name table for text mode.
1 - Undefined
2 - Base of pattern generator table for text mode. 40 * 24
3 - Undefined
4 - Undefined _
5 - Base of name table for text mode.
6 - Base of color table for text mode.
7 - Base of pattern generator table for text mode. 32 * 24
8 - Base of sprite attribute table for text mode.
9 - Base of sprite pattern table for text mode. _
10 - Base of name table for high-resolution mode.
11 - Base of color table for high-resolution mode.
12 - Base of pattern generator table for high-resolution mode.
13 - Base of sprite attribute table for high-resolution mode.
14 - Base of sprite pattern table for high-resolution mode.
15 - Base of name table for multi-color mode.
16 - Undefined
17 - Base of pattern generator table for multi-color mode.
18 - Base of sprite attribute table for multi-color mode.
19 - Base of sprite pattern table for multi-color mode.
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MSX BASIC REFERENCE GUIDE
2.1.16 Machine Dependent Statements and Functions
**********************lci,ici c ic*****-k**-k1fk**ic*************************
* NOTE *
* The following statements and functions access the system's *
* I/O port directly. Programs that use those statements and *
* functions will thus not be compatible with MSX systems *
* released in the future. Programs distributed to the public *
* should not use those statements and functions. *
* *
OUT <port number>,Cinteger expression>
Sends a byte to a machine output port.
<port number> and Cinteger expression> are in the range 0 to
255. Cinteger expression> is the data byte to be transmitted.
WAIT Cport number>,I[,J]
Suspends program execution while monitoring the status of a
machine input port.
The WAIT statement causes execution to be suspended until a
specified machine input port develops a specified bit pattern.
The data read at the port is exclusive OR 1 ed with the integer
expression J, and then is AND'ed with integer expression I. If
the result is zero, BASIC loops back and reads the data at the
port again. If the result is non-zero, execution continues with
the next statement. If j is omitted, it is assumed as zero.
INPKport number>I)
Returns the byte read from the port I. I must be in the range
0 to 255. INP is the complementary function to the OUT
statement.
NOTE
In the above statements and functions, Cport number> is handled
with a 16-bit number to support the Z-80 capability to access
I/O ports with the [BC] register pair, however, standard MSX
systems do not support these extended I/O address spaces, and
port numbers larger than 255 are undefined.
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MSX BASIC REFERENCE GUIDE
2.1.17 Summary of Error Codes and Error Messages
Code Message
1 NEXT without FOR
A variable in a NEXT statement does not
correspond to any previously executed, unmatched
FOR statement variable.
2 Syntax error
A line is encountered that contains some
incorrect sequence of characters (such as
unmatched parenthesis, misspelled command or
statement, incorrect punctuation, etc.)
3 RETURN without GOSUB
A RETURN statement is encountered for which
there is no previous, unmatched GOSUB statement.
4 Out Of DATA
A READ statement is executed when there are
no DATA statement with unread data remaining
in the program.
5 Illegal function call
A parameter that is out of the range is passed
to a math or string function. An FC error
may also occur due to the following causes:
1. A negative or unreasonably large subscript.
2. A negative or zero argument with LOG.
3. A negative argument to SQR.
4. An improper argument to MID?, LEFT$, RIGHT?,
INP, OUT, PEEK, POKE, TAB, SPC, STRING?,
SPACE?, INSTR? or ON...GOTO.
6 Overflow
The result of a calculation is too large to
be represented in BASIC's number format.
7 Out of memory
A program is too large, has too many files,
has too many FOR loops or GOSUBs, too many
variables, or expressions that are too
compl icated.
8
Undefined line number
A line reference
IF. .. THEN. .. ELSE is to
in a GOTO,
a nonexistent
GOSUB,
1 ine.
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MSX BASIC REFERENCE GUIDE
9 Subscript out of range
An array element is referenced either with
a subscript that is outside the dimensions
of the array, or with the wrong number of
subscripts.
10 Redimensioned array
Two DIM statements are given for the same array,
or DIM statement is given for an array after
the default dimension of 10 has been established
for that array.
11 Division by zero
A division by zero is encountered in an
expression, or the operation of involution
results in zero being raised to a negative
power.
12 Illegal direct
A statement that is illegal in direct mode
is entered as a direct mode command.
13 Type mismatch
A string variable name is assigned a numeric
value or vice versa; a function that expects
a numeric argument is given a string argument
or vice versa.
14 Out of string space
String variables have caused BASIC to exceed
the amount of free memory remaining. BASIC
will allocate string space dynamically, until
it runs out of memory.
15 String too long
An attempt is made to create a string more
than 255 character long.
16 String formula too complex
A string expression is too long or too complex.
The expression should be broken into smaller
expressions.
17 Can't continue
An attempt is made to continue a program that:
1. has halted due to an error,
2. has been modified during a break in
execution, or
3. does not exist.
18 Undefined user function
FN function is called before defining it with
the DEF FN statement.
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MSX BASIC REFERENCE GUIDE
19 Device I/O error
An I/O error occurred on a cassette, printer,
or CRT operation. It is a fatal error; i.e.,
BASIC cannot recover from the error.
20 Verify error
The current program is different from the
program saved on the cassette.
21 No RESUME
An error trapping routine is entered but
contains no RESUME statement.
22 RESUME without error
A RESUME statement is encountered before an
error trapping routine is entered.
23 Unprintable error
An error message is not available for the error
condition which exists. This is usually caused
by an ERROR with an undefined error code.
24 Missing operand
An expression contained an operator with no
operand following it.
25 Line buffer overflow
An entered line has too many characters.
26 Unprintable errors
. These codes have no definitions. These are
49 reserved for future expansion of BASIC.
50 FIELD overflow
A FIELD statement is attempting allocate more
bytes than were specified for the record length
of a random file in the OPEN statement. Or,
the end of the FIELD buffer is encountered
while doing sequential I/O (PRINT#, INPUT#) to
a random file.
51 Internal error
An internal malfunction has occurred. Report
to Microsoft the conditions under which the
message appeared.
52 Bad file number
A statement or command references a file with
a file number that is not OPEN or is out of
the range of file numbers specified by MAXFILE
statement.
53 File not found
A LOAD, KILL, or OPEN statement references
a file that does not exist in the memory.
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MSX BASIC REFERENCE GUIDE
54 File already open
A sequential output mode OPEN is issued for
a file that is already open; or a KILL is given
for a file that is open.
55 Input past end
An INPUT statement is executed after all the
data in the file has been INPUT, or for null
(empty) file. To avoid this error, use the
EOF function to detect the end of file.
56 Bad file name
An illegal form is used for the file name with
LOAD, SAVE, KILL, NAME, etc.
57 Direct statement in file
A direct statement is encountered while LOADing
an ASCII format
file.
The LOAD
is
terminated.
Sequential I/O only
A statement to
random
access
is
issued for
a sequential file.
59 File not OPEN
The file specified in a PRINT#, INPUT#, etc.
hasn't been OPENed.
60 Unprintable error
. These codes have no definitions. Users may
place their own error code definitions at the
255 high end of this range.
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MSX BASIC REFERENCE GUIDE
2.1.18 MSX BASIC Reserved Words
The following is a list of reserved words used in MSX BASIC. Hote
that the words with asterisk (*) are reserved for future expansion
only and not explained anywhere in this book.
ABS
AND
ASC
*ATTR $
ATN
AUTO
BASE
BEEP
BINS
BLOAD
BSAVE
CALL
CDBL
CHR$
CINT
CIRCLE
CLEAR
CLOAD
CLOSE
CL S
*CMD
COLOR
CONT
copy
COS
CSAVE
CSNG
CSRLIN
CVD
CVI
CVS
DATA
DEF
DEFDBL
DEFINT
DEFSNG
DEFSTR
DELETE
DIM
DRAW
DSKF
DSKI $
DSKO
ELSE
END
EOF
EQV
ERASE
ERL
ERR
ERROR
EXP
FIELD
FILES
FIX
FN
FOR
FPOS
FRE
GET
GO TO
GOSUB
GOTO
HEX?
IF
IMP
INKEY?
INP
INPUT
INSTR
INT
*IPL
KEY
KILL
LEFT?
LEN
LET
LFILES
LINE
LIST
LLIST
LOAD
LOC
LOCATE
LOF
LOG
LPOS
LPRINT
LSET
MAX
MERGE
MID?
MKD?
MKI $
MKS ?
MOD
MOTOR
NAME
NEW
NEXT
NOT
OCT?
OFF
ON
OPEN
OR
OUT
PAD
PAINT
PDL
PEEK
PLAY
POINT
POKE
POS
PRESET
PRINT
PSET
PUT
READ
REM
RENUM
RESTORE
RESUME
RETURN
RIGHT?
RND
RSET
RUN
SAVE
SCREEN
*SET
SGN
SIN
SOUND
SPACE?
SPC(
SPRITE
SQR
STEP
STICK
STOP
STR?
STRIG
STRING ?
SWAP
TAB (
TAN
THEN
TIME
TO
TROFF
TRON
USING
USR
VAL
VARPTR
VDP
VPEEK
VPOKE
WAIT
WIDTH
XOR
109
ADVANCED PROGRAMMING GUIDE
2.2 Advanced Programming Guide
2.2.1 BIOS Entry List
COMMENT %
The following Restarts (RSTs 0 through RST 5) are reserved for
the BASIC interpreter, RST 6 for inter-slot calls, RST 7 for
hardware interrupt.
The following notation is used in the descriptions.
Name
Name of function
Function
Function to be performed
Entry
Entry parameters
Returns
Returned parameters
Modifies
Registers to be modified
Notes
(optional)
Name:
CHKRAM
Function:
Checks RAM and sets slot for command area.
Entry:
None
Returns:
None
Modifies:
All
Note:
When done, a jump to INIT must be made for
further initialization.
DI
;For fail safe
ENTR CHKRAM
DW CGTABL
;Address of character generator table
DB VDP.DR
;Address of VDP data register (read)
DB VDP.nw
;Address of VDP data register (write)
Name:
SYNCHR
Function:
Checks if the current character pointed by
HL is the one desired. If not, generates
’Syntax error', otherwise falls into CHRGTR.
Entry:
HL, character to be checked be placed at the
next location to this RST.
Returns:
HL points to next character, A has the
character.
Carry flag set if number, Z flag set if end
of statement.
Modifies:
AF, HL
ENTR SYNCHR
HOLE 1
Name:
RDSLT
110
ADVANCED PROGRAMMING GUIDE
Function: Selects the appropriate slot according to the
value given through registers, and reads the
contents of memory from the slot.
Entry: A: FxxxSSPP
I Mil
I I I LJ — Primary slot # (0-3)
I lj -Secondary slot # (0-3)
i- i if secondary slot # specified
; Returns:
; Modifies:
; Note:
}
000C ENT RDSLT
HOLE 1
HL: Address of target memory
A : Contents of memory
AF, BC, DE
Interrupts are disabled automatically
are never enabled by this routine.
but
Name:
Function:
Entry:
Returns:
Modifies:
CHRGTR
Gets next character (or token) from BASIC text
HL
HL points to next character, A has the
character. Carry flag set if number, Z flag
set if end of statement encountered.
AF, HL
0010 ENTR CHRGTR
HOLE 1
Name:
Function:
Entry:
Returns:
Modifies:
Note:
WRSLT
Selects the appropriate slot according to the
value given through registers, and writes to
memory.
A; FxxxSSPP
I till
I i I — Primary slot # (0-3)
I lx - Secondary slot # (0-3)
L -1 if secondary slot # specified
HL: Address of target memory
E : Data to be written
None
AF, BC, D
Interrupts are disabled automatically but
are never enabled by this routine.
000C ENT WRSLT
HOLE 1
Name;
Function:
Entry:
Returns:
Modifies:
OUTDO
Outputs to the current device.
A, PTRFIL, PRTFLG
None
None
111
ADVANCED PROGRAMMING GUIDE
0018 ENT OUTDO
CALSLT
Performs inter-slot call to specified address.
IY -FxxxSSPP
(HIGH) I IMI
I I I *- J — Primary slot # (0-3)
I lx - Secondary slot # (0-3)
1 -1 if secondary slot # specified
IX : Address to call
None
None
Interrupts are disabled automatically but
never enabled by this routine. Arguments can
never be passed via the alternate registers of
the 2-80 or IX and IY.
001C ENT CALSLT
HOLE 1
/
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
0020 ENTR DCOMPR
HOLE 1
/
; Name:
; Function:
Entry:
Returns:
Modifies:
Note:
0024 ENT ENASLT
HOLE 1
t
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
GETYPR
Returns the type of FAC.
FAC
Flags
AF
ENASLT
Selects the appropriate slot according to the
value given through registers, and permanently
enables the slot.
A: FxxxSSPP
I I I I I
I I I *- J -— Primary slot # (0-3)
I lx -Secondary slot # (0-3)
i- 1 if secondary slot # specified
HL: Address of target memory
None
All
Interrupts are disabled automatically but
are never enabled by this routine.
DCOMPR
Compares HL with DE.
HL, DE
Flags
AF
HOLE 1
Name:
Function:
Entry:
Returns:
Modifies:
Note:
112
ADVANCED PROGRAMMING GUIDE
0028 ENTR GETYPR
; The following 5 bytes are reserved to store the MSX version
; number. The first versions hold 5 zeros.
HOLE 5
; Name: CALLF
; Function: Performs far_call (i.e., inter-slot call)
; Entry: None
; Returns: Flags
; Modifies: AF
; Note: The calling sequence is as follows.
•
• RST 6
• DB Destination slot
• DW Destination address
; For a precise description of the parameters,
j see CALSLT.
0030 ENTR CALLF
HOLE 5
KEYINT
Performs hardware interrupt procedures.
None
None
None
0038 ENTR KEYINT
Name:
Function:
Entry:
Returns:
Modifies:
113
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used for I/O initialization.
; Name: INITIO
* Function: Perforins device initialization.
; Entry: None
; Returns: None
; Modifies: All
«
003B ENT INITIO
; Name: INIFNK
; Function: Initializes function key strings.
; Entry: None
; Returns: None
; Modifies: All
«
003E ENT INIFNK
114
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used to access the VDP (TI9918).
; Name: DISSCR
; Function: Disables screen display.
; Entry: None
; Returns: None
; Modifies: AF, BC
0041 ENT DISSCR
*
; Name: ENASCR
; Function: Enables screen display.
; Entry: None
; Returns: None
; Modifies: AF, BC
0044 ENT ENASCR
j Name: WRTVDP
; Function: Writes to the VDP register.
; Entry: Register # in [C], data in tB]
; Returns: None
} Modifies: AF, BC
0047 ENT WRTVDP
; Name: RDVRM
; Function: Reads the VRAM addressed by IHL].
; Entry: HL
; Returns: A
; Modifies: AF
004A ENT RDVRM
t
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
004D ENT WRTVRM
•
r
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
0050 ENT SETRD
; Name: SETWRT
SETRD
Sets up the VDP for read.
HL
None
AF
WRTVRM
Writes to the VRAM addressed by [HLl.
HL, A
None
AF
115
ADVANCED PROGRAMMING GUIDE
Function:
Sets
: Entry:
HL
: Returns:
None
; Modifies:
AF
up the VDP for write.
0053
ENT
SETWRT
Name:
Function:
Entry:
Returns:
Modifies:
FILVRM
Fills the VRAM with the specified data.
Address in tHL], length in [BC], data in [Accl
None
AF, BC
0056
ENT
FILVRM
Name:
Function:
Entry:
Returns:
Modifies:
LDIRKV
Moves a VRAM memory block to memory.
Address of source in [HL], destination in [DE],
length in [BC].
None
All
005
ENT
LDIRMV
Name:
Function:
Entry:
Returns:
Modifies:
LDIRVM
Moves block of memory from memory to the VRAM.
Address of source in [HL], destination in [DE],
length in [BC].
None
All
005C
ENT
LDIRVM
Name:
Function:
Entry:
Returns:
Modifies:
CHGMOD
Sets the VDP mode according to SCRMOD.
SCRMOD (0..3)
None
All
005F
ENT
CHGMOD
CHGCLR
Changes the color of the screen.
Foreground color in FORCLR
Background color in BAKCLR
Border color in BDRCLR
None
All
0062 ENT CHGCLR
HOLE 1
Name:
Function:
Entry:
Returns:
Modifies:
Name:
Function:
Entry:
NMI
Performs non-maskable interrupt procedures.
None
116
ADVANCED PROGRAMMING GUIDE
0066
0069
006C
006F
Returns:
Modifies:
Name;
Function:
None
None
CLRSPR
Initializes all sprites.
Patterns are set to nulls,
set to sprite plane number,
set to foreground color,
sprite names are
sprite colors are
vertical positions
Entry:
are set to 209.
SCRMOD
Returns:
None
Modifies:
All
ENT CLRSPR
Name:
INITXT
Function:
Initializes screen for
text mode (40*24)
Entry:
sets the VDP.
TXTNAM, TXTCGP
Returns:
None
Modifies:
All
ENT INITXT
Name:
INIT32
Function:
Initializes screen for
text mode (32*24)
Entry:
sets the VDP.
T32NAM, T3 2CGP, T32C0L,
T3 2ATR, T32PAT
Returns:
None
Modifies:
All
ENT INIT32
Name:
INIGRP
Function:
Initializes screen for
high-resolution
Entry:
and sets the VDP.
GRPNAM, GRPCGP, GRPCOL,
GRPATR, GRPPAT
Returns:
None
Modifies:
All
ENT INIGRP
Name:
INIMLT
Function:
Initializes screen for
multicolor mode
Entry:
sets the VDP.
MLTNAM, MLTCGP, MLTCOL,
MLTATR, MLTPAT
Returns:
None
Modifies:
All
5 ENT
INIMLT
Name:
Function:
SETTXT
Sets the VDP for text (40*24) mode.
117
ADVANCED PROGRAMMING GUIDE
7 Entry: TXTNAM, TXTCGP
7 Returns: None
; Modifies: All
0078 ENT SETTXT
♦
9
; Name: SETT32
; Function: Sets the VDP for text (32*24) mode.
; Entry: T32NAM, T32CGP, T32C0L, T32ATR, T32PAT
7 Returns: None
7 Modifies: All
007B ENT SETT32
r
7 Name:
7 Function:
; Entry:
; Returns:
? Modifies:
007E ENT SETGRP
J
; Name:
; Function:
7 Entry:
; Returns:
7 Modifies:
•
0081 ENT SETMLT
t
7 Name:
? Function:
? Entry:
; Returns:
? Modifies:
*
00 84 ENT CALPAT
f
} Name:
; Function:
? Entry:
7 Returns:
; Modifies:
00 87 ENT CALATR
/
7 Name: GSPSIZ
? Function: Returns the current sprite size.
7 Entry: None
7 Returns: Sprite size (# of bytes) in [Acc]
7 Carry set if 16*16 sprite in use, otherwise
7 reset the otherwise.
7 Modifies: AF
■
00 8A ENT GSPSIZ
CALATR
Returns address of sprite attribute table.
Sprite ID in [Acc]
Address in [HL]
AF, DE, HL
CALPAT
Returns address of sprite pattern table.
Sprite ID in [Acc]
Address in [HL]
AF, DE, HL
SETMLT
Sets the VDP for multicolor mode.
MLTNAM, MLTCGP, ML T COL, MLTATR, ML T PAT
None
All
SETGRP
Sets the VDP for high-resolution mode.
GRPNAM, GRPCGP, GRPCOL, GRPATR, GRPPAT
None
All
118
ADVANCED PROGRAMMING GUIDE
; Name: GRPPRT
; Function: Prints a character on the graphic screen.
• Entry: Code to output in [Acc]
; Returns: None
; Modifies: None
•
i
008D ENT GRPPRT
119
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used to access the PSG.
0090
00 93
0096
0099
Names
GICINI
Function:
Initializes PSG, and static data for
statement.
Entry:
None
Returns:
None
Modifies:
All
ENT GICINI
Name:
WRTPSG
Function:
Writes data to the PSG register.
Entry:
Register number in [Acc], data in
[E]
Returns:
None
Modifies:
None
ENT WRTPSG
Name:
RDPSG
Function:
Reads data from the PSG register.
Entry:
Register number in [Acc]
Returns:
Data in [Acc]
Modifies:
None
ENT RDPSG
Name:
STRTMS
Function:
Checks/starts background tasks for
PLAY.
Entry:
None
Returns:
None
Modifies:
ENT STRTMS
All
PLAY
120
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used to access the console, i.e., the
keyboard and the CRT.
%
>
; Name:
? Function:
? Entry:
; Returns:
; Modifies:
009C ENT CHSNS
7
; Name:
; Function:
7
; Entry:
; Returns:
; Modifies:
ft
009F ENT CHGET
/
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
$
00 A2 ENT CHPUT
ft
/
? Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
/
00A5 ENT LPTOUT
9
; Name:
; Function:
; Entry:
; Returns:
ft
9
? Modifies:
00A8 ENT LPTSTT
; Name: CNVCHR
j Function: Checks graphic header byte and converts codes.
; Entry: Character code in [Acc]
; Returns: Cy flag reset: graphic header byte
; Cy and Z flags set, converted graphic code
; Cy flag set, Z flag reset, non-converted code
LPTSTT
Checks the line printer status.
None
255 in [Acc] and Z flag reset if printer ready,
0 and Z flag set if not.
AF
LPTOUT
Outputs a character to the line printer.
Character code to be output in [Acc]
Carry flag set if aborted.
F
CHPUT
Outputs a character to the console.
Character code to be output in [Acc]
None
None
CHGET
Waits for characters being input and returns
the character codes.
None
Character code in [Acc]
AF
CHSNS
Checks the status of keyboard buffer.
None
Z flag reset if any character in buffer.
AF
121
ADVANCED PROGRAMMING GUIDE
Modifies: AF
00 AB
ENT
CNVCHR
Name:
Function:
Entry:
Returns:
Modifies:
PINLIN
Accepts a line from console until a CR or STOP
is typed, and stores the line in a buffer.
None
Address of buffer top-1 in [HL], carry flag
set if STOP is input.
All
00AE ENT
PINLIN
Name:
Function:
Entry:
Returns:
Modifies:
INLIN
Same as PINLIN, except if AUTFLG is set.
None
Address of buffer top-1 in [HLl, carry
set if STOP is input.
All
flag
00B1
ENT
INLIN
Name:
Function:
Entry:
Returns:
Modifies:
QINLIN
Outputs a '?' mark and a space then falls into
the INLIN routine.
None
Address of buffer top-1 in [HLl, carry flag
set if STOP is input.
All
00B4
ENT
QINLIN
Name:
Function:
Entry:
Returns:
Modifies:
Note:
BREAKX
Checks the status of the Control-STOP key.
None
Carry flag set if being pressed.
AF
This routine is used to check Control-STOP
when interrupts are disabled.
00B7 ENT
BREAKX
Name:
Function:
Entry:
Returns:
Modifies:
ISCNTC
Checks the status of the SHIFT-STOP key.
None
None
None
00BA ENT
ISCNTC
Name:
Function:
Entry:
Returns:
CKCNTC
Same as ISCNTC, used by BASIC.
None
None
122
ADVANCED PROGRAMMING GUIDE
r
m
OOBD
00C0
OOC3
00C6
00C9
OOCC
OOCF
Modifies:
None
ENT CKCNTC
Name:
BEEP
Function:
Sounds the
buzzer.
Entry:
None
Returns:
None
Modifies:
All
ENT BEEP
Name:
CLS
Function:
Clears the
screen.
Entry:
None
Returns:
None
Modifies:
AF, BC, DE
ENT CLS
Name:
POSIT
Function:
Locates the cursor at the specified position.
Entry:
Column in
[H] , row in [L]
Returns:
None
Modifies:
AF
ENT POSIT
Name:
FNKSB
Function:
Checks if
function key display is active. If
it is, it
displays it, otherwise does nothing.
Entry:
FNKFLG
Returns:
None
Modifies:
All
ENT FNKSB
Name:
ERAFNK
Function:
Erases the
function key display.
Entry:
None
Returns:
None
Modifies:
All
ENT ERAFNK
Name:
DSPFNK
Function:
Displays the function key display.
Entry:
None
Returns:
None
Modifies:
All
ENT DSPFNK
Name:
TOTEXT
Function:
Forcibly places the screen in text mode.
123
ADVANCED PROGRAMMING GUIDE
; Entry:
; Returns:
; Modifies:
00D2 ENT TOTEXT
None
None
All
124
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used for game I/O access.
; Name:
; Function;
; Entry;
; Returns:
; Modifies;
m
t
00D5 ENT GTSTCK
i
; Name;
; Function;
; Entry:
; Returns:
i
; Modifies:
OOD8 ENT GTTRIG
7
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
*
OODB ENT GTPAD
*
; Name: GTPDL
; Function: Returns the value of the paddle.
; Entry: Paddle ID in [Acc]
; Returns: Value in [Acc]
; Modifies: All
OODE ENT GTPDL
GTPAD
Checks the current touch PAD status.
ID in [Acc]
Value in [Acc]
All
GTTRIG
Returns the current trigger button status.
Trigger button ID in [Acc]
Returns 0 in [Acc] if not pressed, 255
otherwise.
AF
GTSTCK
Returns the current joystick status.
Joystick ID in [Acc]
Direction in [Acc]
All
125
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used to access the cassette tape.
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
00El ENT TAPION
,
; Name: TAPIN
; Function: Inputs from tape.
; Entry: None
; Returns: Data in [Acc], carry flag set if aborted.
; Modifies: All
00E4 ENT TAPIN
; Name: TAPIOF
; Function: Stops reading from tape.
; Entry: None
; Returns: None
; Modifies: None
♦
00E7 ENT TAPIOF
*
f
; Name:
; Function:
i
; Entry:
♦
/
; Returns:
; Modifies:
00EA ENT TAPOON
/
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
00ED ENT TAPOUT
; Name: TAPOOF
i Function: Stops writing to tape.
; Entry; None
; Returns: None
; Modifies: None
OOFO ENT TAPOOF
TAPOUT
Outputs to tape.
Data to be output in [Acc]
Carry flag set if aborted.
All
TAPOON
Sets motor on and writes header block to
cassette.
[Acc] holds non-0 value if a long header
desired, 0 if a short header desired.
Carry flag set if aborted.
All
TAPION
Sets motor on and reads header from tape.
None
Carry flag set if aborted.
All
126
ADVANCED PROGRAMMING GUIDE
STMOTR
Starts the cassette motor.
0 in [Acc] to stop, 1 to start, 255 to flip.
None
AF
00F3 ENT STMOTR
Name:
Function:
Entry:
Returns:
Modifies:
127
AEVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used to handle queues.
%
; Name; LFTQ
f Function: Returns the number of bytes left in the queue.
; Entry:
; Returns:
; Modifies:
♦
OOF6 ENT LFTQ
f
; Name: PUTQ
; Function: Places a byte in the queue.
; Entry:
; Returns:
; Modifies:
OOF9 ENT PUTQ
128
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are used by the GENGRP and
modules.
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
OOFC ENT RIGHTC
9
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
9
OOFF ENT LEFTC
*
9
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
/
0102 ENT UPC
*
9
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
9
0105 ENT TUPC
*
/
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
010 8 ENT DOWNC
9
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
010B ENT TDOWNC
RIGHTC
Moves one pixel right
LEFTC
Moves one pixel left.
UPC
Moves one pixel up.
TUPC
Moves one pixel up.
DOWNC
Moves one pixel down.
TDOWNC
Moves one pixel down.
ADVGRP
129
ADVANCED PROGRAMMING GUIDE
; Name: SCALXY
; Function: Scales the X-Y coordinates.
; Entry:
; Returns:
; Modifies:
♦
010E ENT SCALXY
; Name: MAPXYC
; Function: Maps the coordinate to the physical address.
; Entry:
; Returns:
; Modifies:
0111 ENT MAPXYC
Name:
Function:
FETCHC
Fetches
current
physical address and mask
Entry:
Returns:
pattern.
None
Address
in [HLl ,
mask pattern in [Acc]
Modifies:
A, HL
0114 ENT FETCHC
«
i
} Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
0117 ENT STOREC
}
; Name: SETATR
; Function: Sets attribute byte.
; Entry:
; Returns:
; Modifies:
«
OilA ENT SETATR
♦
9
t Name:
; Function:
? Entry:
; Returns:
; Modifies:
•
011D ENT READC
r
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
READC
Reads attribute of current pixel.
SETC
Sets current pixel to the specified attribute.
STOREC
Stores physical address and mask pattern.
Address in [HLJ , mask pattern in [Accl
None
None
130
ADVANCED PROGRAMMING GUIDE
0120 ENT SETC
1 Name: NSETCX
? Function: Sets pixels horizontally.
; Entry:
7 Returns:
; Modifies:
0123 ENT NSETCX
♦
; Name: GTASPC
; Function: Returns the aspect ratio.
; Entry: None
; Returns: DE, HL
; Modifies: DE, HL
0126 ENT GTASPC
•
? Name: PNTINI
7 Function: Initializes the PAINT function.
7 Entry:
? Returns:
? Modifies:
0129 ENT PNTINI
i
7 Name: SCANR
7 Function: Scans pixels to the right.
7 Entry:
7 Returns:
7 Modifies:
■
012C ENT SCANR
7 Name: SCANL
7 Function: Scans pixels to the left.
7 Entry:
7 Returns:
7 Modifies:
012F ENT SCANL
131
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following routines are additional entries.
f Name:
; Function:
; Entry:
♦
f
; Returns:
; Modifies:
0132 ENT CHGCAP
?
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
0135 ENT CHGSND
; Name: RSLREG
; Function: Reads the current output to the primary slot
• register.
; Entry: None
; Returns: Result in [Acc]
; Modifies: A
CHGSND
Changes the status of the 1 bit sound port.
0 in [Acc] to turn off, non-0 otherwise.
None
AF
CHGCAP
Changes the status of CAP lamp.
0 in [Acc] to turn off the lamp, non-0
otherwise.
None
AF
013 8 ENT RSLREG
? Name: WSLREG
? Function: Writes to the primary slot register.
} Entry: Value in [Acc]
; Returns: None
; Modifies: None
013B ENT WSLREG
*
/
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
013E ENT RDVDP
§
; Name: SNSMAT
j Function: Returns the status of a specified row of a
f keyboard matrix.
; Entry: Row # in [Acc]
; Returns: Status in [Acc], corresponding bit is reset
; to 0 if a key is being pressed.
; Modifies: AF
RDVDP
Reads the VDP status register.
None
Data in [Accl
A
132
ADVANCED PROGRAMMING GUIDE
0141 ENT SNSMAT
; Name: PHYDIO
Function: Performs operation for mass-storage devices
; such as disks.
; Entry:
; Returns:
; Modifies:
; Note: In the minimum configuration, only a hook is
; provided.
0144 ENT PHYDIO
♦
; Name: FORMAT
; Function: Initializes mass-storage devices.
; Entry:
; Returns:
; Modifies:
; Note: In the minimum configuration, only a hook is
j provided.
•
0147 ENT FORMAT
t
; Name:
; Function:
; Entry:
; Returns:
; Modifies:
•
/
014A ENT ISFLIO
; Name: OUTDLP
; Function: Outputs to the line printer.
; Entry: Code in [Acc]
; Returns: None
; Modifies: F
; Note: This entry differs from LPTOUT in that:
; 1) TABS are expanded to spaces,
; 2) Hiragana and graphics are converted when
• a non-MSX printer is in use,
; 3) A jump to 'Device I/O error' is made when
; aborted.
*
014D ENT OUTDLP
; Name: GETVCP
; Function:
; Entry:
; Returns:
; Modifies:
; Note: Used only to play music in the background.
0150 ENT GETVCP
ISFLIO
Checks if device I/O is being done.
None
Non-zero if so, zero otherwise.
AF
133
ADVANCED PROGRAMMING GUIDE
; Name: GETVC2
; Function:
; Entry:
; Returns:
j Modifies:
; Note: Used only to play music in the background.
♦
0153 ENT GETVC2
*
i
; Name:
; Function:
? Entry:
; Returns:
; Modifies:
0156 ENT KILBUF
#
; Name:
; Function:
•
i
; Entry:
? Returns:
; Modifies:
0159 ENT CALBAS
/
; The following is a patch area for BIOS. It is placed here to
; make it easier to add new entry vectors.
HOLE 90
CALBAS
Performs far_call (i.e., inter-slot call) into
the BASIC interpreter.
Address in [1X1
KILBUF
Clears the keyboard buffer.
None
None
HL
134
ADVANCED PROGRAMMING GUIDE
2.2.2 Work Area
•
9
The following short routines
•
i
write and call functions.
7
PPI.AW==&B10101000
#
7
Read primitive
F380
RMB(RDPRIM, 5)
OUT
PPI.AW
MOV
E, M
JMPR
WRPRMl
•
i
*
i
Write primitive
F385
RMB(WRPRIM, 7)
OUT
PPI.AW
MOV
M,E
WRPRM1: MOV
A, D
OUT
PPI.AW
RET
7
7
Call primitive
F38C
RMB (CLPRIM, 14)
OUT
PPI.AW
EXAF
CALL
CLPRIM+12
EXAF
POP
PSW
OUT
PPI.AW
EXAF
RET
IX
PCHL
F39A
RMB(USRTAB, 20)
DW
FCERR
DW
FCERR
DW
FCERR
DW
FCERR
DW
FCERR
DW
FCERR
DW
FCERR
DW
FCERR
DW
FCERR
DW
FCERR
F3AE
RMB (LINL40 ,1)
DB
39
F3AF
RMB(LINL32,1)
DB
LINLN
F3B0
RMB(LINLEN, 1)
DB
LINLN
perform the inter-slot read/
;A8H Write to PPI Port A
Select primary slot
Read from slot
Restore current setting
;Select primary slot
;Write to slot
;Load current setting
jRestore current setting
;Select primary slot
;Restore [Acc] and flags
;Perform indirect call by IX
;Save possible returned value
;Get old slot status
;Restore it
;Restore possible returned
;value
;Line length
135
ADVANCED PROGRAMMING GUIDE
F3B1 RMB(CRTCNT, 1)
DB 24 ;Line count
F3B2 RMB(CLMLST, 1)
DB 14
Beginning of MSX-specific work area
F3B3
RMB(TXTNAM,
2)
DW1
&B00000000000000+$CODE
;0000H
F3B5
RMB(TXTCOL,
2)
DWl
&BOOOOOOOOOOOOOQ+$CODE
*
t
Unused
F3B7
RMB (TXTCGP,
2)
DWl
&B00100000000000+5CODE
;0800 H
F3B9
RMB(TXTATR,
2)
DWl
&BO0000000000000+$CODE
•
f
Unused
F3BB
RMB(TXTPAT,
2)
DWl
&booooooooqooooo+$code
•
t
Unused
F3BD
RMB(T32NAM,
2)
DWl
&BOHOOOOOOOOOOO+$CODE
;1800H
F3BF
RMB(T3 2COL,
2)
DWl
&B10000000000000+$CODE
;2000H
F3C1
RMB (T32CGP,
2)
DWl
&B00000000000000+$CODE
;0000H
F3C3
RMB(T32ATR,
2)
DWl
&B01101100000000+$CODE
?1B00H
F3C5
RMB(T3 2PAT,
2)
DWl
&B1HOOOOOOOOOOO+$CODE
; 3 80 OH
F3C7
RMB(GRPNAM,
2)
DWl
&B01100000000000+$CODE
; 180 OH
F3C9
RMB(GRPCOL,
2)
DWl
&B10000000000000 + $ CODE
; 2000H
F3CB
RMB (GRPCGP,
2)
DWl
&BOOOOOOOOOOOOOO+$CODE
; 0000H
F3CD
RMB(GRPATR,
2)
DWl
&boiioiioooooooo+$code
;1B00H
F3CF
RMB(GRPPAT,
2)
DWl
&B11100000000000+$CODE
;3800H
F3D1
RMB(MLTNAM,
2)
DWl
&B00100000000000+SCODE
; 0800H
F3D3
RMB(MLTCOL,
2)
DWl
&B00000000000000+$CODE
i
Unused
F3D5
RMB (MLTCGP,
2)
DWl
&B00000000000000+SCODE
; OOOOH
F3D7
RMB(MLTATR,
2)
DWl
&B01101100000000+$CODE
; 1B00H
F3D9
RMB(MLTPAT,
2)
DWl
&B11100000000000+$CODE
; 3 80 0 H
F3DB
RMB(CLIKSW,
1)
DB
1
F3DC
RMB(CSRY,
1)
DB
1 ;Cursor position
y
136
ADVANCED PROGRAMMING GUIDE
F3DD RMB(CSRX, 1)
DB 1 ;Cursor position X
F3DE RMB(CNSDFG, 1)
DB 0 ;Function key display switch
*
/
; Save area for the VDP registers
F3DF RMB(RGOSAV, 1)
DB 0
F3E0 RMB(RG1SAV, 1)
DB &B11100000
F3E1 RMB (RG2SAV, 1)
DB 0
F3E2 RMB(RG3SAV, 1)
DB 0
F3E3 RMB(RG4SAV, 1)
DB 0
F3E4 RMB(RG5 SAV, 1)
DB 0
F3E5 RMB(RG6SAV, 1)
DB 0
F3E6 RMB(RG7 SAV, 1)
DB 0
F3E7 RMB(STATFL, 1)
DB 0
♦
F3E8 RMB(TRGFLG, 1)
DB &B11111111
F3E9 RMB (FOR CL R, 1)
DB 15 ;Foreground color, default is white
F3EA RMB(BAKCLR, 1)
DB 4 background color, default is blue
F3EB RMB (BDRCLR, 1)
DB 7 ;Screen border color
F3EC RMB(MAXUPD, 3)
JMP SCODE
F3EF RMB(MINUPD, 3)
JMP $CODE
F3F2 RMB(ATRBYT, 1)
DB 15 ;Attribute byte
F3F3 RMB(QUEUES, 2)
DWl QUETAB ;Address of QUEUTL queue tables
F3F5 RMB(FRCNEW, 1)
DB 255
F3F6 RMB(SCNCNT, 1)
DB 1 ;Interval of keyscan
F3F7 RMB(REPCNT, 1)
DB 50
F3F8 RMB (PUTPNT, 2)
DWl KEYBUF
F3FA RMB(GETPNT, 2)
DWl KEYBUF
F3FC RMB(CS120, 5*2)
137
ADVANCED PROGRAMMING GUIDE
; Some parameters for cassette
I
HEDLEN= 2000 ;Length of header bits (mark) for short
{header
7
; The following parameters are for 1200 baud.
*
INTERN LOW01,HIGH01,LOW11,HIGH11
LOW01= 83 {Width of low state for 0
HIGH01= 92 {Width of high state for 0
LOW11= 38 {Width of low state for 1
HIGH11= 45 ;Width of high state for 1
DB LOW01
DB HIGH01
DB LOWll
DB HIGH11
DB HEDLEN *2/256
i
} The following parameters are for 2400 baud.
•
INTERN LOW02, HIGH02 , LCW12, HIG HI 2
LOW02= 37 ;Width of low state for 0 1200Hz-
;416.7 usee
HIGHO2= 45 ;Width of high state for 0
L0W12= 14 ;Width of low state for 1 2400Hz-
{208.3 usee
HIG HI 2*= 22 {Width of high state for 1
DB LOW02
DB HIGHO2
DB LCW12
DB HIGH12
DB HEDLEN*4/256
F406 RMB(LOW, 2)
DB LCW01 {Default 1200 baud
DB HIGH01
P40 8 RMB ( HIGH, 2)
DB LOWll
DB HIG HI 1
F40A RMB (HEADER, 1)
DB HEDLEN*2/256 ;Default 1200 baud
F40B RMB(ASPCT1, 2)
DWl $CODE+256 ;256/aspect ratio
F40D RMB(ASPCT2, 2)
DWl $CODE+256 ?256*aspect ratio
9
; ENDPRG must be the last one which needs initializing
F40F RMB(ENDPRG, 5)
DB {Dummy program end for RESUME NEXT
9
; End of initialized constants
•
INTERN INILEN
INILEN= ENDPRG+1-INIRAM {Length of initialized data
138
ADVANCED PROGRAMMING GUIDE
F414 RMB(ERRFLG, 1)
F415 RMB(LPTPOS, 1)
F416 RMB(PRTFLG, 1)
F417 RMB (NTMSXP, 1)
F418 RMB(RAWPRT, 1)
F419 RMB (VLZ ADR, 2)
F41B RMB(VLZDAT, 1)
F41C RMB(CURLIN, 2)
ZX== ZX+1
F41F RMB (KBUF, KBFLEN)
F55D RMB(BUFMIN, 1)
F55E RMB(BUF, BUFLEN+3)
F660 RMB(ENDBUF, 1)
F661 RMB(TTYPOS, 1)
F662 RMB(DIMFLG, 1)
F663 RMB(VALTYP, I)
F664 RMB(OPRTYP, 0)
F664 RMB(DORES, 1)
F665 RMB(DONUM, 1)
F666 RMB(CONTXT, 2)
F668 RMB(CONSAV, 1)
F669 RMB(CONTYP, 1)
F66A RMB(CONLO, 8)
F672 RMB(MEMSIZ, 2)
F67 4 RMB(STKTOP, 2)
F676 RMB(TXTTAB, 2)
{Used to save the error number
;Position of printer head: initially
;0
{Whether output goes to LPT
;Non-0 if not 1 MSX-printer'
{Non-0 if printing is in 'raw-mode'
{Address of character replaced by VAL
{Character replaced by 0 by VAL
This is the crunch buffer.
Since the data pointer always starts
on commas or terminators, commas (pre¬
load or ROM) are used by INPUTS.
Type in stored here. Direct statements
execute out of here. Remember "INPUT"
destroys BUF. Must be at a lower
address than DSCTMP, or assignment
of string values in direct statements
won't copy into string space — which
it must.
Place to stop big lines
Store terminal position here
In getting a pointer to a variable
it is important to remember whether
it is being done for a "DIM" or not.
DIMFLG and VALTYP must be consecutive
locations.
Type indicator
Used to store operator number in the
extended momentarily before operator
application (APPLOP)
Whether can or can't crunch reserved
words turned on in the 8K when "DATA"
is being scanned by CRUNCH, thus un¬
quoted strings won't be crunched.
Flag for CRUNCH =0 means numbers
allowed, (floating, INT, DBL) 1 means
numbers allowed, CRUNCH by calling
LINGET -1 (377) means numbers
not allowed (scanning variable name).
Saved text pointer used by CHRGET to
save the text pointer after a constant
has been scanned.
The saved token for a constant after
CHRGET has been called.
Saved constant VALTYPE
Saved constant VALUE
Highest location in memory
Top location to be used for the stack,
(initially set up by INIT depending
on memory size to allow for 50 bytes
of string space. Changed by a CLEAR
command with arguments.
Pointer of beginning of text does not
139
ADVANCED PROGRAMMING GUIDE
F67 8 RMB(TEMPPT, 2)
F67A RMB(TEMPST, 3*NUMTMP)
F698 RMB(DSCTMP# 3)
INTERN DSCPTR
DSCPTR= DSCTMP+1
F69B RMB(FRETOP, 2)
F69D RMB(TEMP3, 2)
F69F RMB(TEMP8, 2)
F6A1 RMB(ENDFOR, 2)
F6A3 RMB(DATLIN, 2)
F6A5 RMB(SUBFLG, 1)
F6A6 RMB(USFLG, 0)
F6A6 RMB(FLGINP, 1)
F6A7 RMB(TEMP, 2)
F6A9 RMB(PTRFLG, 1)
F6AA RMB(AUTFLG, 1)
F6AB RMB(AUTLIN, 2)
F6AD RMB(AUTINC, 2)
F6AF RMB(SAVTXT, 2)
F6B1 RMB (SAVSTK, 2)
F6B3 RMB(ERRLIN, 2)
F6B5 RMB(DOT, 2)
F6B7 RMB(ERRTXT, 2)
F6B9 RMB(ONELIN, 2)
F6BB RMB(ONEFLG, 1)
F6BC RMB(TEMP2, 2)
F6BE RMB(OLDLIN, 2)
;change after being set up by INIT.
;Pointer at first free temporary des¬
criptor initialized to point to TEMPST
;Storage for NUMTMP temp, descriptors
;String functions build answer
;descriptor here must be after TEMPST
;and before PARM1.
;Where in DSCTMP string address stored
;Top of string free space
;Used to store the address of the end
;of string arrays in garbage collection
;and used momentarily by FRMEVL used
;in EXTENDED by FOUT and user defined
;functions and array variable handling
temporarily.
;7/3/79 Now used for garbage collection
?not TEMP3 due to conflict
;Saved text pointer at end of "FOR"
;statement
;DATA LINE # — remember ERRORS
;Flag whether subscripted variable
;allowed "FOR" and USR-defined function
;Pointer fetching turn this on before
calling PTRGET so arrays won't be
{detected. STKINI and PTRGET clear it.
{Flag for INPUT or READ
{Temporary for statement code. NEWSTT
{saves [H,L] here for INPUT and ''C,
{"LET" saves variable pointers here,
{for "FOR-NEXT" saves its text pointer
{here, CLEARC saves [H,Ll here.
{=0 If no line numbers converted to
{pointers, non-zero if pointers exist.
{Flag to indicate AUTO command in
{progress, =0 if not, non-zero if so.
{Current line being inserted by AUTO
{AUTO increment
{Place where NEWSTT saves text pointer
;for "RESUME" statement
{NEWSTT saves stack here before so
{that error recovery can restore the
{stack when an error occurs.
{Line number where last error occured.
{Keeps current line for edit & LIST
{Text pointer for use by "RESUME"
{Line to GOTO when an error occurs.
{ONEFLG=l if executing an error trap
{routine, otherwise 0.
{Formula evaluator temp. Must be pre-
{served by operators used in EXTENDED
{by FOUT and user-defined functions
;array variable handler temporary
{Old line number (set up by *C, "STOP”
140
ADVANCED PROGRAMMING GUIDE
F6C0 RMB(OLDTXT, 2)
F6C2 RMB(VARTAB, 2)
P6C4 RMB(ARYTAB, 2)
F6C6 RMB(STREND, 2)
F6C8 RMB(DATPTR, 2)
F6CA RMB(DEFTBL, 26)
or "END" in a program).
Old text pointer. Points at statement
to be executed next.
Pointer to start of simple variable
space. Updated whenever the size of
the program changes, set to [TXTTAB]+2
by SCRATCH ("NEW").
Pointer to beginning of array table.
Incremented by 6 whenever a new simple
variable is found, and set to [VARTAB]
by CLEARC.
End of storage in use. Increased
whenever a new array or a simple
variable is encountered, set to
[VARTAB] by CLEARC.
Pointer to data. Initialized to point
at the zero in front of [TXTTAB] by
"RESTORE" which is called by CLEARC,
updated by execution of a "READ"
This gives the default VALTYP for
each letter of the alphabet. It is
set up by "CLEAR" and is changed by
"DEFSTR", "DEFINT", "DEFSNG", "DEFDBL"
and used by PTRGET when ! # % or
$ do not follow a variable name.
RAM storage for user—defined function parameter information
INTERN PRMSIZ
PRMSIZ==~D100
F6E4 RMB(PRMSTK, 2)
F6E6 RMB(PRMLEN, 2)
F6E8 RMB(PARM1, PRMSIZ)
F74C RMB(PRMPRV, 2)
F74E RMB (PRMLN2 , 2)
F750 RMB(PARM2, PRMSIZ)
F7B4 RMB(PRMFLG, 1)
F7B5 RMB(ARYTA2, 2)
F7B7 RMB(NOFUNS, 1)
F7B8 RMB(TEMP9, 2)
F7BA RMB(FUNACT, 2)
F7BC RMB ( SWPTMP, 8)
F7C4 RMB(TRCFLG, 1)
Number of bytes for definition block
Previous definition block on stack
:block (for garbage collection)
Number of bytes in the active table
The active parameter definition table
Initially PRMSTK, the pointer at the
previous parameter block (for garbage
icollection)
Size of parameter block being built
Place to keep parameters being made
Used by PTRGET to flag if PARM1 has
been searched
Stopping point for simple search
' (either [ARYTAB] or PARMl+tPRMLEN])
Zero if no functions active. Saves
TIME in simple search
Garbage collection temp. to chain
through parameter blocks.
Count of active functions
Value of first "SWAP" variable stored
here
Zero means no trace in progress
This is the RAM temporary area for the math package routines
F7C5 RMB(FBUFFR, 43) ;Buffer for FOUT
141
ADVANCED PROGRAMMING GUIDE
F7F0 RMB(DECTMP, 2) ;Used by decimal int to float
F7F2 RMB(DECTM2, 2) ;Used by divide
F7F4 RMB(DECCNT, 1) ;Used by divide
#
; Decimal accumulator
#
ZX== ZX+1 ;Temporary sign complement
F7F6 RMB(DAC, 16)
INTERN FACLO
FACLO= DAC+2
4
/
; Holding registers for decimal multiplication
F806
RMB(HOLD8,
48)
; 80 *X
F836
RMB(HOLD2 ,
8)
; 2*X
F83E
RMB(HOLD,
8)
; 1*X
; Argument accumulator
f
ZX== ZX+1 ;Temporary sign complement
F847 RMB(ARG, 16)
F857 RMB(RNDX, 8) ;Holds last random number generated
142
ADVANCED PROGRAMMING GUIDE
SUBTTL Data Area
♦
/
; Set up by initialization. Unchanged by disk code.
F85F RMB(MAXFIL, 1) {Highest legal file number
F860 RMB(FILTAB, 2) ;Points to adress of file data
F862 RMB(NULBUF, 2) ;Points to file 0 buffer
*
t
; Set up by file / drive selection routines. Only PTRFIL is
; cleared elsewhere.
•
r
F864 RMB(PTRFIL, 2) {Points to file data of selected file
#
; Misc.
r
F866 RMB(RUNFLG, 0) ;Non-zero for RUN after LOAD
F866 RMB(FILNAM,11) {Holds filename for DIRSRC, from NAMSCN
F871 RMB(FILNM2,11) {Holds other filename for NAME
F87C RMB(NLONLY, 1) {Non-zero when loading program
t
{ Set up by NULOPN and BSAVE, used by BSAVE and CREATE.
t
F87D RMBCSAVEND, 2) {End of binary or memory image save
F87F RMB(FNKSTR, 16*10) {Function key string save area
F91F RMB(CGPNT, 3) {Where character pattern is held in ROM
F922 RMB(NAMBAS,2) {Base of current name table
F924 RMB(CGPBAS,2) {Base of current cgen table
F926 RMB(PATBAS,2) {Base of current sprite pattern table
F928 RMB(ATRBAS,2) {Base of current sprite attribute table
r
{ For GENGRP
m
F92A RMB (CLOC, 2)
F92C RMB(CMASK, 1)
F92D RMB(MINDEL,2)
F92F RMB (MAXDEL»2)
j For CIRCLE
F931 RMB(ASPECT,2)
F933 RMB (CENCNT, 2)
F93 5 RMB(CLINEF,1)
F936 RMB(CNPNTS,2)
F93 8 RMB(CPLOTF,1)
F939 RMB (CPCNT, 2)
F93B RMB (CPCNT8,2)
F93D RMB (CRCSUM, 2)
F93F RMB(CSTCNT,2)
F941 RMB(CSCLXY,1)
F942 RMB(CSAVEA,2)
F944 RMB (CSAVEM, 1)
F945 RMB(CXOFF, 2)
F947 RMB(CYOFF, 2)
9
Aspect ratio for circle
End count
Flag to draw line to center
Points to plot
Plot polarity flag
1/8 of number of points in circle
Number of pts in circle
Circle sum
Start count
Scaling of x and y
ADVGRP C save area
ADVGRP C save area
X offset from center save location
Y offset save location
143
ADVANCED PROGRAMMING GUIDE
; For PAINT
•
F949 RMB(LOHMSK,!)
F94A RMB(LOHDIR,l)
F94B RMB(LOHADR,2)
F94D RMB(LOHCNT,2)
F94F RMB(SKPCNT,2)
F951 RMB(MOVCNT,2)
F953 RMB(PDIREC,1)
F954 RMB(LFPROG,!)
F955 RMB(RTPROG,1)
; For MACLNG
F956 RMB(MCLTAB,2)
F958 RMB(MCLFLG/1) ;Indicates PLAY/DRAW
; QUEUES for PLAY statement
F959 RMB(QUETAB, A D24) ;4 queues (6 bytes each)
F97I RMB(QUEBAK,~D4) ;For BCKQ
MUSQLN=: *012 8 ;Size of voice queues
RSIQLN=:''D64
F97 5 RMB (VOICAQ, MUSQLN) ;Voice a queue
F9F5 RMB (VOICBQ, MUSQLN) ;Voice b queue
FA75 RMB (VOICCQ,MUSQLN) ;Voice C queue
FAF5 RMB(RS2IQ, RSIQLN) ;RS232 input queue
7
; Music stuff
;RAM save area for left overhang
;Skip count
;Move count
;Paint direction
FB35 RMB(PRSCNT,1) ;D1-D0 = number of strings parsed
;D7=0 if first pass, 1 if not
FB36 RMB(SAVSP, 2) ;Save main stack pointer During play
FB38 RMB(VOICEN,1) ;Set current voice being parsed
FB3 9 RMB (SAWOL, 2) ;Save volume for pause
FB3B RMB (MCLLEN, 1)
FB3C RMB(MCLPTR,2)
FB3E RMB(QUEUEN,1) ;Used by intime-action-dequeue
FB3F RMB(MUSICF,1) ;Music interrupt flag
FB40 RMB(PLYCNT,!) ;Number of play statements queued for
;background task
7
; Per Voice Static Data Area Displacement Definitions
METREX=:0
VCXLEN=:METREX+2
VCXPTR=:VCXLEN+1
V CXS T P=:V CXPTR+2
QLENGX=:VCXSTP+2
NTICSX=:QLENGX+1
TONPRX=:NTICSX+2
AMPLTX=:TONPRX+2
ENVPRX=: AMPLTX+1
0CTAVX=:ENVPRX+2
} Timer countdown
;MCLLEN for this voice
;MCLPTR for this voice
;Save top of stack pointer
;Number of bytes to be queued
;New countdown
;Tone period
;Amplitude/shape
; Envelope period
;Octave
144
ADVANCED PROGRAMMING GUIDE
NOTELX=: OCTAVX+1
TEMPOX=:NOTELX+1
VOLUMX=;TEMPOX+1
ENVLPX=:VOLUMX+l
MCLSTX=:ENVLPX+ A DI4
MCLSEX=:MCLSTX+3
VCBSIZ = :MCLSEX-METREX+1
FB41 RMB(VCBA, VCBSIZ)
PB 66 RMB(VCBB, VCBSIZ)
FB 8 B RMB(VCBC, VCBSIZ)
;Note length
? Tempo
;Volume
;Envelope shape
;Stack save area
; Initial stack
;Voice static buffer size
jStatic data for voice 0
;Static data for voice 1
?Static data for voice 2
Area between here and MUSICF is cleared everytime a IGICIN
is called.
FBBO RMB(ENSTOP,l)
FBB1 RMB(BASROM, 1)
FBB2 RMB(LINTTB/2 4)
FBCA RMB(FSTPOS,2)
FBCC RMB(CODSAV,1)
FBCD RMB (FNKSWI,1)
FBCE RMB(FNKFLG,10)
FBD8 RMB (ONGSBF,l)
FBD9 RMB(CLIKFL,1)
FBDA RMB(OLDKEY,11)
FBE5 RMB ( NEWKEY, 11)
INTERN SFTKEY
SFTKEY= NEWKEY+6
FBFO RMB (KEYBUF, 40)
FC18 RMB(BUFEND,0)
FC18 RMB(LINWRK,40)
FC40 RMB(PATWRK,8)
FC48 RMB(BOTTOM,2)
FC4A RMB(HIMEM, 2)
FC4C RMB (TRPTBL, 3 *NUMTRP)
FC9A RMB(RTYCNT,1)
FC9B RMB(INTFLG,1)
FC9C RMB(PADY, 1)
FC9D RMB(PADX, 1)
FC9E RMB(JIFFY, 2)
FCAO RMB(INTVAL,2)
FCA2 RMB(INTCNT,2)
FCA4 RMB(LCWLIM,1)
FCA5 RMB(WINWID,1)
FCA6 RMB(GRPH ED,1)
FCA7 RMB(ESCCNT,1)
FCA8 RMB(INSFLG,1)
FCA9 RMB(CSRSW, 1)
FCAA RMB(CSTYLE,1)
FCAB RMB(CAPST, 1)
FCAC RMB(KANAST,1)
FCAD RMB(KANAMD,1)
FCAE RMB(FLBMEM,1)
FCAF RMB(SCRMOD,1)
;Non-zero if warm start enabled
;Non-zero if BASIC text is in ROM
;Line terminator table
7 First position when entered INLIN
7 Code save area for cursor
7 Indicates which function key is
;dislayed
7 Indicates key is assigned to event
?device
;Global event flag
7 Old key status
;New key status
,*GR,CTRL, SHIFT status
?Key code buffer
7 End of KEYBUF
7 Scratch area for screen handler
7 Scratch area for pattern converter
7 Bottom of equipped RAM
?Highest available memory
;Trap table
;Used when reading cassette
7 Used when reading cassette
7 Flag for graphic character output
;Escape sequence counter
;Insert mode flag
7 Cursor display switch
7 Cursor style
7 Capital status
7 Kana lock status
,-Non-O if JIS
70 if loading BASIC program
7 Screen mode
145
ADVANCED PROGRAMMING GUIDE
;(0-ext,1-text,2-hires,2-multi)
FCBO RMB(OLDSCR,l) ;Screen mode save area
FCBl RMB(CASPRV,1) ;Previous character save area for CAS:
FCB2 RMB(BRDATR,1) ;Border color for PAINT
FCB3 RMB(GXPOS, 2)
FCB5 RMB(GYPOS, 2)
FCB7 RMB(GRPACX,2) ;Graphic accumulater
FCB9 RMB(GRPACY,2)
FCBB RMB(DRWFLG , 1>
FCBC RMB(DRWSCL,1) ;Draw scale factor - 0 means no scaling
FCBD RMB(DRWANG,1) {Draw angle (0-3)
; For BLOAD and BSAVE
m
FCBE RMB(RUNBNF,1) j Doing BLOAD, BSAVE or not
FCBF RMB(SAVENT,2) ;Start address for BSAVE
i
} Information save area for slots
FCC1 RMB(EXPTBL, 4) ;Flag table for expanded slot
;Holds 255 if expanded
FCC5 RMB(SLTTBL, 4) } Current setting for each expanded
;slot register
FCC9 RMB(SLTATR, 64) ;Holds attributes for each slot
FD09 RMB(SLTWRK, 128) ?Holds work area specific for each slot
f
; For CALL statement and device expander
*
FD89 RMB(PROCNM,16) ;Name of expanded statement terminated
;by 0
FD99 RMB(DEVICE, 1) ;The device ID for a cartridge (0 to 3)
146
ADVANCED PROGRAMMING GUIDE
COMMENT %
The following are definitions of hooks and their functions:
Name - Name of hook
Location - Location in module it is used
Purpose - Use
%
GSX== ZX
FD9A RMB(HOKJMP, 0)
9
; Name: H.KEYI
; Location: MSXIO, at the beginning of interrupt handler
; Purpose: Does additional interrupt handling such as
7 RS-232C.
FD9A RMB (H.KEYI, 5)
9
7 Name: H.TIMI
7 Location: MSXIO, in timer interrupt handler
7 Purpose: Allows other interrupt handling invoked by
; timer.
FD9F RMB(H.TIMI,5)
7
7 Name: H.CHPU
7 Location: MSXIO, at the beginning of CHPUT (CHaracter
7 outPUT) routine.
7 Purpose: Allows for other console output devices.
■
FDA4 RMB (H.CHPU, 5)
9
; Name: H.DSPC
7 Location: MSXIO, at the beginning of DSPCSR (DiSPlay
7 CurSoR) routine.
7 Purpose: Allows for other console output devices.
•
f
FDA9 RMB (H.DSPC, 5)
9
7 Name: H.ERAC
7 Location: MSXIO, at the beginning of ERACSR (ERAse
7 CurSoR) routine.
7 Purpose: Allows for other console output devices.
FDAE RMB(H.ERAC,5)
7 Name; H.DSPF
7 Location: MSXIO, at the beginning of DSPFNK (Display
7 FuNction Key) routine.
7 Purpose: Allows for other console output devices.
FDB3 RMB(H.DSPF,5)
147
ADVANCED PROGRAMMING GUIDE
Name:
Location:
FDB8
FDBD
FDC2
FDC7
FDCC
FDD1
Purpose:
RMBCH.ERAF,5)
Name:
Location:
Purpose:
RMB(H.TOTE,5)
Name:
Location:
Purpose:
RMB (H. CHGE, 5)
Name:
Location:
Purpose:
RMB(H.INIP,5)
Name:
Location:
Purpose:
RMB(H.KEYC,5)
Name:
Location:
Purpose:
RMBCH.KYEA,5)
Name:
Location:
Purpose:
FDD6 RMBCH.NMI, 5)
Name:
Location:
Purpose:
H.ERAF
MSXIO, at the beginning of ERAFNK (ERAse
FuNction Key) routine.
Allows for other console output devices.
H.TOTE
MSXIO, at the beginning of TOTEXT (force
screen TO TEXT mode) routine.
Allows for other console output devices.
H. CHGE
MSXIO, at the beginning of CHGET (CHaracter
GET) routine.
Allows for other console input devices.
H.INIP
MSXIO,at the beginning of INIPAT (INItialize
PATtern) routine.
Allows for other character sets.
H.KEYC
MSXIO, at the beginning of KEYCOD (KEY
CODer) routine.
Allows for other key assignments.
H.KYEA
MSXIO, at the beginning of KYEASY (KeY EASY)
routine.
Allows for other key assignments.
H. NMI
MSXIO, at the beginning of NMI (Non Maskable
Interrupt) routine.
Allows for NMI handling.
H.PINL
MSXINL, at the beginning of PINLIN (Program
INput LINe) routine.
Allows other console input devices or other
input designs to be used.
148
ADVANCED PROGRAMMING GUIDE
FDDB RMB(H.PINL,5)
f
; Name:
; Location:
?
; Purpose:
i
FDEO RMB(H.QINL,5)
I
; Name:
; Location:
■
9
; Purpose:
FDE5 RMB(H.INLI,5)
Name:
Location:
; Purpose:
FDEA RMB (H. ONGO, 5)
; Name:
; Location:
t
; Purpose:
•
9
FDEF RMB(H.DSK0,5)
9
} Name:
; Location:
«
9
; Purpose:
*
FDF4 RMB(H.SETS,5)
Name:
Location:
Purpose:
FDF9 RMB(H.NAME,5)
Name:
Location:
; Purpose:
FDFE RMB(H.KILL,5)
Name:
Location:
H.QINL
MSXINL, at the beginning of QINLIN (Question
mark and INput LINe) routine.
Allows other console input devices or other
input designs to be used.
H.INLI
MSXINL, at the beginning of INLIN (INput
LINe) routine.
Allows other console input devices or other
input designs to be used.
H.ONGO
MSXSTS, at the beginning of ONGOTP (ON GOTo
Procedure) routine.
Allows for other console input devices to be
used.
H.DSKO
MSXSTS, at the beginning of DSKO$ (DiSK
Output) routine.
Installs the disk driver.
H. SETS
MSXSTS, at the beginning of SETS (SET
attributes) routine.
Installs the disk driver.
H. NAME
MSXSTS, at the NAME (reNAME) routine.
Installs the disk driver.
H.KILL
MSXSTS, at the beginning of KILL (KILL
file) routine.
Installs the disk driver.
H. I PL
MSXSTS, at the beginning of IPL (Initial
Program Load) routine.
149
ADVANCED PROGRAMMING GUIDE
; Purpose:
FE03 RMB ( H. IPL, 5)
#
/
; Name:
? Location:
7
; Purpose:
FE08 RMB(H.C0PY,5)
9
; Name:
? Location:
•
9
; Purpose:
m
FEOD RMB(H.CMD, 5)
9
; Name:
; Location:
•
/
; Purpose:
FE12 RMB(H.DSKF,5)
■
r
; Name:
; Location:
•
t
; Purpose:
FE17 RMB(H.DSKI,5)
/
; Name:
; Location:
•
I
; Purpose:
FE1C RMB(H.ATTR, 5)
t
; Name:
; Location:
•
9
; Purpose:
FE21 RMB(H. LSET,5)
9
; Name:
; Location:
*
9
; Purpose:
FE26 RMB(H.RSET,5)
♦
9
; Name:
; Location:
Installs the disk driver.
H.COPY
MSXSTS, at the beginning of COPY (COPY
file) routine.
Installs the disk driver.
H. CMD
MSXSTS, at the beginning of CMD (CoMmanD)
routine.
Installs the disk driver.
H.DSKF
MSXSTS, at the beginning of DSKF (DiSK Free)
routine.
Installs the disk driver.
H. DSKI
MSXSTS, at the beginning of DSKI (DiSK
Input) routine.
Installs the disk driver.
H.ATTR
MSXSTS,at the beginning of ATTR$ (ATTRibute)
routine.
Installs the disk driver.
H.LSET
MSXSTS, at the beginning of LSET (Left SET)
routine.
Installs the disk driver.
H.RSET
MSXSTS, at the beginning of RSET (Right SET)
routine.
Installs the disk driver.
H.FIEL
MSXSTS, at the beginning of FIELD (FIELD)
150
ADVANCED PROGRAMMING GUIDE
; Purpose:
/
FE2B RMB(H.FIEL,5)
t
; Name:
; Location:
■
/
; Purpose:
FE3 0 RMB(H.MKI$,5)
?
; Name:
; Location:
t
i Purpose:
FE35 RMB(H.MKS $ ,5)
/
; Name:
; Location:
*
f
; Purpose:
•
FE3 A RMB (H. MKD$ ,5)
f
; Name:
; Location:
/
; Purpose:
■
FE3F RMB(H. CV1,5)
!
; Name:
; Location:
•
i
; Purpose:
FE44 RMB(H.CVS,5)
t
; Name:
; Location:
♦
i
; Purpose:
•
FE49 RMB(H.CVD,5)
routine.
Installs the disk driver.
H.MKI$
MSXSTS, at the beginning of MKI$ (MaKe Int)
routine.
Installs the disk driver.
H.MKS $
MSXSTS, at the beginning of MKS$ (Make
Single) routine.
Installs the disk driver.
H.MKD $
MSXSTS, at the beginning of MKD$ (Make
Double) routine.
Installs the disk driver.
H.CVI
MSXSTS, at the beginning of CVI (Convert
Int) routine.
Installs the disk driver.
H. CVS
MSXSTS, at the beginning of CVS (Convert
Sng) routine.
Installs the disk driver.
H.CVD
MSXSTS, at the beginning of CVD (Convert
Dbl) routine.
Installs the disk driver.
151
ADVANCED PROGRAMMING GUIDE
Name:
Location:
Purpose:
FE4E
RMB(H.GETP,5)
; Name:
7 Location:
; Purpose:
FE53 RMB(H.SETF,5)
9
; Name:
; Location:
7 Purpose:
*
FES8 RMB (H. NOFO, 5)
Name:
Location:
Purpose:
FE5D
RMB (H. NUL0,5)
Name:
Location:
Purpose:
FE6 2
RMB (H. NTFL,5)
Name:
Location:
; Purpose:
FE67 RMB(H.MERGES)
f
; Name:
; Location:
? Purpose:
FE6C RMB (H. SAVE, 5)
; Name:
7 Location:
7 Purpose:
FE71 RMB(H.BINS,5)
♦
/
7 Name:
7 Location:
7 Purpose:
FE76 RMB ( H. BINL, 5)
H.GETP
SPCDSK, at the GETPTR (GET file PoinTeR).
Installs the disk driver.
H.SETF
SPCDSK, at the SETFIL (SET FILe pointer).
Installs the disk driver.
H.NOFO
SPCDSK, at the NOFOR (NO FOR clause) routine.
Installs the disk driver.
H.NULO
SPCDSK,at the NULOPN (NUL1 file OPeN)routine.
Installs the disk driver.
H.NTFL
SPCDSK, at the NTFLO (NoT FiLe number 0).
Installs the disk driver.
H.MERG
SPCDSK, at the MERGE (MERGE program files)
routine.
Installs the disk driver.
H.SAVE
SPCDSK, at the SAVE routine.
Installs the disk driver.
H.BINS
SPCDSK, at the BINSAV (BINary SAVe) routine.
Installs the disk driver.
H.BINL
SPCDSK, at the BINLOD (BINary LOaD) routine.
Installs the disk driver.
152
ADVANCED PROGRAMMING GUIDE
; Name:
; Location:
; Purpose:
FE7B RMB(H.FILE,5)
v
/
; Name:
; Location:
; Purpose:
FE80 RMB (H. DGET, 5)
t
; Name:
; Location:
; Purpose:
FE85 RMB(H.FILO,5)
9
; Nam e:
; Location:
Purpose:
FE8A
RMB(H.INDS,5)
? Name:
; Location:
; Purpose:
FE8F RMB(H.RSLF,5)
7
; Name:
; Location:
; Purpose:
FE94 RMB(H.SAVD,5)
Name:
Location:
Purpose:
FE99
RMB(H.LOC,
5)
Name:
Location:
Purpose:
FE9E
RMB(H.LOF,
5)
Name:
Location:
Purpose:
FEA3
RMB(H.EOF,
5)
H.FILE
SPCDSK, at the FILES command.
Installs the disk driver.
H. DGET
SPCDSK, at the DGET (Disk GET) routine.
Installs the disk driver.
H.FILO
SPCDSK, at the FILOUl (FILe OUt 1) routine.
Installs the disk driver.
H.INDS
SPCDSK, at the INDSKC (INput DiSK Character)
routine.
Installs the disk driver.
H.RSLF
SPCDSK, to re-select the old drive.
Installs the disk driver.
H.SAVD
SPCDSK, to save the current drive.
Installs the disk driver.
H.LOC
SPCDSK, at the LOC (Location) function.
Installs the disk driver.
H. LOF
SPCDSK, at the LOF (Length Of File)function.
Installs the disk driver.
H. EOF
SPCDSK, at the EOF (End Of File) function.
Installs the disk driver.
153
ADVANCED PROGRAMMING GUIDE
; Name:
; Location:
; Purpose:
•
FEA8 RMB(H.FPOS,5)
t
; Name:
; Location:
; Purpose:
«
FEAD RMB(H.BAKU,5)
/
; Name:
; Location:
♦
/
; Purpose:
FEB2 RMB(H.PARD, 5)
#
; Name:
; Location:
; Purpose:
FEB7 RMB(H.NODE,5)
7
; Name:
; Location:
; Purpose:
FEBC RMB ( H. POSD, 5)
/
; Name:
; Location:
} Purpose:
FECI RMB ( H. DEVN, 5)
♦
9
; Name:
; Location:
9
; Purpose:
FEC6 RMB(H. GEND,5)
i
; Name;
; Location:
; Purpose:
*
FECB RMB (H. RUNC, 5)
*
9
i Name:
; Location:
; Purpose:
4
/
FEDO RMB(H.CLEA,5)
H.FPOS
SPCDSK, at FPOS (File Position) function.
Installs the disk driver.
H.BAKU
SPCDSK, at the BAKUPT (BAcK UP) routine.
Installs the disk driver.
H.PARD
SPCDEV, at the PARDEV (PARse DEVice name)
routine.
Epands logical device names.
H. NODE
SPCDEV, at the NODEVN(NO DEVice Name)routine
Sets other default devices.
H.POSD
SPCDEV, at the POSDSK (POSsibly DiSK)routine
Installs the disk driver.
H. DEVN
SPCDEV, at the DEVNAM (DEVice NAMe) routine.
Expands logical device names.
H.GEND
SPCDEV, at the GENDSP (GENeral device
Dispatcher).
Expands logical device names.
H.RUNC
BIMISC, at the RUNC (RUN Clear) routine.
H.CLEA
BIMISC, at the CLEARC (CLEAR Clear) routine.
154
ADVANCED PROGRAMMING GUIDE
; Name:
; Location:
•
9
; Purpose:
FED5 RMB(H.LOPD,5)
9
; Name:
; Location:
} Purpose:
*
FEDA RMB(H.STKE,5)
9
; Name:
; Location:
f Purpose:
FEDF RMB(H.ISFL,5)
; Name:
; Location:
; Purpose:
9
FEE4 RMB(H.OUTD,5)
9
; Name:
; Location:
i Purpose:
♦
FEES RMB(H.CRDO,5)
9
? Name:
; Location:
i Purpose;
FEEE RMB(H.DSKC,5)
/
; Name:
; Location:
; Purpose:
FEF3 RMB (H. DOGR, 5)
Name:
Location:
Purpose:
FEF8
RMB (H. PRGE, 5)
Name:
Location:
Purpose;
H.LOPD
BIMISC, at the LOPDFT (LOop and set DeFaulT)
routine.
Uses other defaults for variables.
H. STKE
BIMISC, at the STKERR (STacK ERRor) routine.
H.ISFL
BIMISC, at the ISFLIO (IS FiLe I/O) routine.
H.OUTD
BIO, at the OUTDO (OUT DO) routine.
H.CRDO
BIO, at the CRDO (CRlf DO) routine.
R.DSKC
BIO, at the DSKCHI (DiSK CHaracter Input)
routine.
H.DOGR
GENGRP, at the DOGRPH (DO GRaPH) routine.
H.PRGE
BINTRP, at the PRGEND (PRoGram END) routine.
H.ERRP
BINTRP, at the ERRPRT (ERRor PRinT) routine.
155
ADVANCED PROGRAMMING GUIDE
FEFD RMB (H. ERRP, 5)
r
; Name:
; Location:
; Purpose:
FF02 RMB(H.ERRF, 5)
*
f
; Name:
; Location:
; Purpose:
FF07 RMB(H.READ, 5)
#
; Name:
; Location:
; Purpose:
FFOC RMB(H.MAIN,5)
i
; Name:
; Location:
; Purpose:
•
FF11 RMB{H.DIRD,5)
#
; Name:
; Location:
j Purpose:
FF16 RMB(H.FINI,5)
/
; Name:
; Location:
; Purpose:
♦
FF1B RMB (H. FINE, 5)
/
; Name:
; Location:
; Purpose:
•
FF20 RMB(H.CRUN,5)
f
; Name:
; Location:
; Purpose:
•
FF25 RMB ( H. CRUS, 5)
9
; Name:
; Location:
; Purpose:
»
FF2A RMB(H.ISRE,5)
BINTRP
H. READ
BINTRP, at the READY entry.
H.MAIN
BINTRP, at the MAIN entry.
H.DIRD
BINTRP, at the DIRDO (DIRect DO) entry.
BINTRP
BINTRP
BINTRP
BINTRP
BINTRP
156
ADVANCED PROGRAMMING GUIDE
; Name:
? Location:
; Purpose:
FF2F RMB(H.NTFN,5)
9
; Name:
; Location:
; Purpose:
♦
FF34 RMB(H.NOTR, 5)
9
; Name:
; Location:
; Purpose:
FF39 RMB ( H. SNGF, 5)
9
; Name:
; Location:
; Purpose:
FF3E RMB(H.NEWS,5)
v
/
; Name:
; Location:
; Purpose:
♦
FF43 RMB(H.GONE,5)
9
t Name:
; Location:
; Purpose:
FF48 RMB(H.CHRG,5)
; Name:
; Location:
; Purpose:
•
FF4D RMB(H.RETU,5)
r
; Name:
; Location:
; Purpose:
FF52 RMB(H.PRTF,5)
r
; Name:
; Location:
; Purpose:
BINTRP
BINTRP
BINTRP
BINTRP
BINTRP
BINTRP
BINTRP
BINTRP
BINTRP
FF57 RMB(H.COMP,5)
ADVANCED PROGRAMMING GUIDE
Name:
Location:
Purpose:
FF5C
RMB(H.FINP, 5)
BINTRP
Name:
Location:
Purpose:
FF61
RMB (H. TRMN, 5)
; Name:
j Location:
; Purpose:
FF66 RMB(H.FRME,5)
9
; Name:
; Location:
; Purpose:
FF6B RMB (H. NTPL, 5)
/
; Name:
; Location:
; Purpose:
FF7
RMB (H. EVAL, 5)
BINTRP
BINTRP
BINTRP
BINTRP
Name:
Location:
Purpose:
FF75
RMB(H.OKNO,5)
; Name:
; Location:
; Purpose:
♦
FF7A RMB(H.FING,5)
$
; Name:
; Location:
; Purpose:
FF7F RMB(H.ISMI,5)
m
9
; Name:
f Location:
j Purpose:
FF84 RMB(H.WIDT,5)
Name:
BINTRP
BINTRP
H. ISMI
BINTRP, at the ISMID? (IS MID$) routine.
H.WIDT
BINTRP, at the WIDTHS (WIDTH) routine.
H.LIST
158
ADVANCED PROGRAMMING GUIDE
; Location:
; Purpose:
FF89 RMB(H.LIST,5)
f
; Name:
; Location:
; Purpose:
FF8E RMB(H.BUFL,5)
r
; Name:
; Location:
; Purpose:
•
9
FF93 RMB(H.FRQ1,5)
/
; Name:
; Location:
; Purpose:
♦
FF98 RMB(H.SCNE,5)
/
; Name:
; Location:
■
i
; Purpose:
•
FF9D RMB(H.FRET,5)
«
9
; Name:
; Location:
; Purpose:
FFA2 RMB(H.PTRG,5)
f
; Name:
; Location:
; Purpose:
FFA7 RMB(H.PH YD,5)
*
9
; Name:
; Location:
; Purpose:
FFAC RMB(H.FORM,5)
♦
9
; Name:
j Location:
; Purpose:
«
FFB1 RMB(H.ERRO,5)
*
9
; Name:
BINTRP, at the LIST routine.
H.BUFL
BINTRP, at the BUFLIN (BUFfer LINe) routine.
H.FRQI
BINTRP, at the FRQINT routine.
BINTRP
H.FRET
BISTRS, at the FRETMP (FREe up TeMPoraries)
routine.
H.PTRG
BIPTRG, at the PTRGET (PoinTeR GET) routine.
Uses other variable names than default.
H. PH YD
MSXIO, at the PHYDIO (PHYsical Disk I/O).
Installs the disk driver.
H.FORM
MSXIO, at the FORMAT (disk FORMATter)routine.
Installs the disk driver.
H.ERRO
BINTRP, at the ERROR routine.
Traps errors from application programs.
H.LPTO
159
ADVANCED PROGRAMMING GUIDE
; Location:
/
7 Purpose:
FFB6 RMB(H.LPTO,5)
♦
i
; Name:
; Location:
*
/
; Purpose:
FFBB RMB(H.LPTS,5)
f
; Name:
; Location:
; Purpose:
FFCO RMB(H.SCRE,5)
7
; Name:
; Location:
; Purpose:
FFC5 RMB(H.PLAY,5)
FFCA RMB(ENDWRK,0)
MSXIO, at the LPTOUT (Line PrinTer OUTput)
routine.
Uses a non-default printer.
H.LPTS
MSXIO, at the LPTSTT (Line PrinTer STaTus)
routine.
Uses a non-default printer.
H.SCRE
MSXSTS, at the entry to SCREEN statement.
Expands the SCREEN statement.
H. PLAY
MSXSTS, at the entry to PLAY statement.
Expands the PLAY statement.
;End of work area.
160
ADVANCED PROGRAMMING GUIDE
2.2.3 Slot Control
[ Memory structure of MSX ]
#0 tl #2 13
“
-
—
—
—
—
—
_
B
A
S
I
—
—
C
—
<Slot #0 expand©d> <Slot II expanded> <Slot 12 expanded> <Slot #3 expanded>
Terminology:
Primary slot:
Secondary slot:
Page:
Slot enabled by the slot select register in
the 8255 PPI.
Slot enabled by the expansion slot register
at OFFFFH.
Memory block (maximum 16K) in each slot. The
slots are divided into four pages (0000H to
3FFFH, 4000H to 7FFFH, 8000H to 0BFFFH , and
0C000H to OFFFFH).
161
cr
ADVANCED PROGRAMMING GUIDE
o Minimum configuration
) Microsoft MSX-BASIC interpreter at slot #0 from 0000H to 7FFFH.
) Minimum of 8K RAM from OEOOOH to OFFFFH in any slot (including
the secondary slot)
o RAM search procedure
MSX-BASIC first searches for available RAM from OBFFFH down
to 08000H (including the secondary slots), then enables the page
with the largest available RAM. If there are more than one such
pages, MSX-BASIC selects the leftmost page in the figure above.
MSX-BASIC next searches for RAM from OFFFFH down to 0C000H, and
does the same procedure. Finally, MSX-BASIC searches for a
continuous RAM block from OFFFFH to 8000H and sets the system
variable 'BOTTOM'.
o PROGRAM CARTRIGE search procedure
MSX-BASIC scans all slots (including secondary slots) from
4000H to OBFFFH for a valid ID at the beginning of each page,
collects information, and passes control to each page. The
scan order is from left to right in the figure above. The
format of the ID and other information are as follows.
Offset from top
+0000H r-T
I ID I
+0002H I-H
I INIT I
+0004H f-4
I STATEMENT I
+0006H h - 4
I DEVICE I
+0008H I- - 4
I TEXT I
+000AH h-4
I I
I Reserved I
I I
+o oi Oh >---
- The ID is a two-byte code used to distinguish the ROM
cartridges from the empty pages by using 'AB' (41H,42H).
- INIT holds the address of the initialization procedure specific
to this cartridge. The default is 0 when no such procedure is
necessary. Programs that need to interact with the BASIC
interpreter should return control to it with a Z-80 'RET'
instruction (all registers except [SP] may be destroyed). Note,
however, that other programs (such as games) do not need to do
this.
162
ADVANCED PROGRAMMING GUIDE
- STATEMENT holds an address of the expanded statement handler
when contained in the cartridge; the address is 0 if no handler
is contained. If BASIC encounters a 'CALL' statement, it calls
this address, with the statement name in the system area.
Note the following points. (In the notes below, the [HLl regis¬
ter pair is called a 'text pointer'.)
1) The cartridge must be placed at 4000H to 7FFFH.
2) The syntax for the expanded statement is as follows.
CALL <statement_name> I ( <arg> I ,<arg> ].. ) ]
The keyword "CALL" can be replaced by an underscore (_).
3) The statement name is stored in the system area,
terminated by a 0. Since the buffer for statement name
is of a fixed length (16 bytes), the statement name
cannot be longer than 15 characters.
4) If the handler for the statement is not contained within
the cartridge, set the carry flag and return. Note that
the text pointer must be returned unchanged.
5) If the handler for that statement is contained within
the cartridge, it should handle the specified function,
update the text pointer to the end of the statement
(Normally it would point to 0, indicating the end of the
line, or to ': ' to indicate the end of the statement),
and return with carry flag reset (all registers except
tSPl may be destroyed). At the entry to the expanded
statement handler, the text pointer should point to the
first non-blank character after the statement name.
- DEVICE holds the address of the expanded device handler if it is
contained in this cartridge. The default is 0 if no handler is
contained. BASIC calls this address with the device name in the
system area. Note the following points.
1) The cartridge must be placed at 4000H to 7FFFH.
2) The device name is stored in the system area terminated
by 0. Since the length of the statement name buffer is
fixed (16 bytes), the device name cannot be longer than
15 characters.
3) Each cartridge (16K) can have up to 4 logical devices.
4) When BASIC encounters an unidentifiable device name, it
it calls the DEVICE entry with OFFH in [Acc]. If the
specified device handler is not contained within the
cartridge, the carry flag should be set upon return. If
the specified device handler is contained inside, the
device ID (0 to 3) should be returned in [Acc], and the
163
ADVANCED PROGRAMMING GUIDE
carry should be reset. All registers may be destroyed.
5) Real I/O operations take place when a DEVICE entry
is entered with one of the following values in [Acc].
0 Open
2 Close
4 Random I/O
6 Sequential output
8 Sequential input
10 LOC function
12 LOF function
14 EOF function
16 FPOS function
18 Back up a character
Device ID is passed in the system variable 'DEVICE'.
- TEXT holds the beginning address of the (tokenized) BASIC text
contained in the cartridge. The default is 0 when no such text
is inside. BASIC regards this as the beginning address of BASIC
text, sets pointer there, and begins execution of the program.
Note the following points.
1) When there is more than one such slot, only the
leftmost one (in the figure above) is enabled and
executed.
2) The cartridge must be placed at 8000H to OBFFFH, thus
the maximum length of BASIC text cannot exceed 16K
bytes.
3) Even if there is a RAM block at 8000H to OBFFFH, it can¬
not be used.
4) The address pointed to by the TEXT entry must contain
a zero.
5) The line numbers (for statements which reference line
numbers, such as GOTO and GOSUB) should be translated to
pointers in advance because they are not converted to
pointers during execution. Note that while they CAN be
line numbers, the execution would be slower.
Note: INIT, STATEMENT, DEVICE and TEXT are placed with the low
order byte first.
164
ADVANCED PROGRAMMING GUIDE
o How slot information is kept in the system area
EXPTBL - Indicates which slot is expanded.
EXPTBL: DS 1 ;for slot #0
DS 1 ;for slot #1
DS 1 ;for slot #2
DS 1 ffor slot #3
Each entry in the EXPTBL holds 80H if expanded, 0 if
not expanded.
SLTTBL - Indicates the value currently output to the expansion
slot register. Valid only when corresponding EXPTBL
holds 80H.
SLTTBL: DS 1 ;for slot #0
DS 1 ;for slot #1
DS 1 ;for slot #2
DS 1 ;for slot #3
SLTATR - Holds attributes for each page.
SLTATR: DS 64
Each byte in the SLTATR table corresponds to each page.
Bits are assigned as follows.
XXXXXXXX
I I I I I I II
I I I I I I I *—Unused
MINI 1 —Unused
Mill 1 -Unused
I l I I i-Unused
I I I 1 -Unused
I l 1 -Statement expander inside
I i-Device expander inside
L -BASIC text inside
SLTWRK - Holds working storage for each page.
SLTWRK: DS 128
Each word in the SLTWRK table can be exclusively used
by each page. The use of this work area depends entirely
on the page.
165
ADVANCED PROGRAMMING GUIDE
o Usage of hooks
Hooks are one of the methods in which MSX-BASIC can be expanded.
Some procedures (such as 'console input', 'console output')
have a Z-80 'CALL' instruction directed to the common RAM area.
The areas consist of a five-byte storage area per hook, and are
initialized with five Z-80 'RET' instructions upon cold start.
Expansion is done by redirecting this entry elsewhere.
Example:
CALL HOOKxx
in ROM
HOOKxx: RET
RET
RET
RET
RET
HOOKxx: RST 6
DB <Slot-address>
in RAM DW <Memory-address>
RET
RST 6 performs an inter-slot call to a different slot.
Refer to BIOENT.MAC for further details of the interslot
call facility.
To connect the hook to the desired routine, the routine
must determine its location (slot). This is important
because the routine's slot location is unpredictable.
This is done by the following procedure.
RSLREG
EQU
138H
EXPTBL
EQU
0FCC1H
B8000
EQU
1
CALL
RRC
RRC
RSLREG
IF
B8000
RRC
RRC
ENDIF
AN I
11B
MOV
C, A
MV I
B, 0
LX I
H,EXPTBL
DAD
B
ORA
M
MOV
C, A
INX
H
INX
H
;Set this true if the
rprogram resides at
;8000 . . OBFFPH
;Read primary slot #
;Move it to bit 0,1
;of [Acc]
;See if this slot is
; expanded or not
;Set MSB if so
?Point to SLTTBL entry
166
ADVANCED PROGRAMMING GUIDE
INX
H
INX
H
MOV
A, M
IF
B8000
RRC
RRC
ENDIF
AN I
1100B
ORA
c
RET
Get what is currently
output to expansion
slot register
Move it to bit 2,3
of [Acc]
Finally form slot
address
< CAUTION >
A machine language program in a cartridge must be able to run
in any slot (including secondary slots). The slot for running
the cartridge is unpredictable.
167
ADVANCED PROGRAMMING GUIDE
o Usage of USR function
There are 10 USR functions, USRO through USR9. USRO can be
abbreviated as USR. The address for a USR function jump is
defined as follows.
DEFUSRO=&HEOOO (This can be DEFUSR=&HE000)
DEFUSR3 *=&HE023
The USR functions can be invoked as follows.
A=USR0(12) (This can also be A=USR(12))
PRINT USR("ABCD")+" This is a test"
The USR function parameters are passed to the machine language
programs in the following manner.
Integer
When USR is called as an integer function, the address
0F663H contains 2, and its value is located at 0F7F8H
and 0F7F9H, with the lower byte first.
String
When USR is called as a string function, the address
0F663H contains 3, and its string descriptor is located
at 0F7F8H and 0F7F9H. String descriptors consist of
three bytes, the first byte is the length of string, the
second and third are the address of the string.
Single-precision
When USR is called as a single-precision function, the
address 0F663H contains 4, and its value is located at
0F7F6H to 0F7F9H.
Double-precis!on
When USR is called as a double—precision function, the
address 0F663H contains 8, and its value is located at
0F7F6H to 0F7FDH.
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ADVANCED PROGRAMMING GUIDE
The value from a USR function can be returned to BASIC in the
following manner.
Integer
The data at the address 0F663H should be set to 2. The
value should be placed in 0F7F8H and 0F7F9H, with the
lower byte first.
String
The data at the address 0F663H should be set to 3. The
address of the string descriptor should be placed in
0F7F8H and 0F7F9H. String descriptors consist of three
bytes, the first byte is set to the string length, the
second and third bytes indicate the string address.
Single-precision
The data at the address 0F663H should be set to 4. The
value should be placed in 0F7F6H through 0F7F9H.
Double-precision
The data at the address 0F663H should be set to 8. The
value should be placed in 0F7F6H through 0F7FDH.
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ADVANCED PROGRAMMING GUIDE
o How to allocate work area for cartridges
If the program is stand-alone (i.e., does not need to run with
other programs in other cartridges), all RAM area below the
fixed work area for BIOS (i.e., below 0F380H) is free. However,
if the program must run with the BASIC interpreter and programs
in other cartridges, the RAM usage is restricted.
There are three ways to allocate RAM to be used exclusively
by each cartridge.
1) Put RAM on the cartridge. (Easiest and best)
2) If the work area is less than 3 bytes, use SLTWRK.
3) If the work area is greater than 2 bytes, make SLTWRK point
to the system variable BOTTOM (0FC48H), then update it by
the amount of memory required. BOTTOM is set by the
initialization code to point to the bottom of the RAM.
Exam pi e:
Program
is at
4000H to 7FFFH
SIZE
EQU
???
;Size of memory required
RSLREG
EQU
138H
EXPTBL
EQU
0FCC1H
BOTTOM
♦
EQU
0FC48H
I
CALL
RSLREG
;Read primary slot #
RRC
;Move it to bit 0,1
RRC
;of tAcc]
AN I
00000011B
MOV
C, A
MV I
B, 0
LXI
H,EXPTBL
;See if this slot is
DAD
B
;expanded or not
ADD
A
ADD
A
ADD
A
ADD
A
MOV
C, A
MOV
A, M
ADD
A
SBB
A
;Form mask pattern
AN I
00001100B
INX
H
;Point to SLTTBL entry
INX
H
INX
H
INX
H
ANA
M
;Get what is currently
;output to expansion
;slot register
ORA
C
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ADVANCED PROGRAMMING GUIDE
ORI 00000001B
Now, we have the sequence number for this
cartridge as follows.
OOPPSSBB
111111
1 1 1 1 ‘■ J — Higher 2 bits
of memory address
1 1 LJ —
- Secondary slot # (0..3)
j-j-
- Primary slot
# (0..3)
ADD
A
;Double since word table
MOV
C, A
MV I
B, 0
;Point to entry in
LXI
H, SLTWRK
DAD
B
;SLTWRK table
LB CD
BOTTOM
;Get current RAM bottom
MOV
M, C
;Register this
INX
H
MOV
M, B
LXI
H,SIZE
DAD
B
MOV
A, H
;Beyond OEFFFH?
CPI
OFOH
j Too much RAM required?
JRNC
NOROOM
;Yes, cannot allocate
SHLD
RET
BOTTOM
BOTTOM
became greater
than OEFFFH, there is
no RAM
left to be allocated.
NOROOM: ;Print messages or
;something like that
171
Note that a pulse begins in the low state when it is being
written.
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ADVANCED PROGRAMMING GUIDE
B. Header
There are two kinds of headers; long headers and short headers.
The long header is used for the file header, and the short
header is used for the body of the file.
I 1200 baud ]
Long header 16000 x 2400 Hz
Short header 4000 x 2400 Hz
C 2400 baud ]
Long header 32000 x 4800 Hz
Short header 8000 x 4800 Hz
The baud rate is determined when reading the header.
C. Data
Data is composed of one 'O' (Start bit) followed by an 8-bit
data stream, and is followed by two 1 l's (Stop bits). The
sequence of the data is from the least significant bit (LSB) to
the most significant bit (MSB). When reading from cassette,
the software measures the number of transitions during 3/4
of the baud rate. The result should be a 1 when reading a space,
or 2 or 3 when reading a mark.
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ADVANCED PROGRAMMING GUIDE
o Logical Format
There three file types (also called file attributes) supported
in MSX-BASIC. These file types, or attributes, are: BASIC text
files, ASCII text files, and machine language files.
A. BASIC Text File Format
[ File header ]
Long header
10 x 0D3H
File name (6 bytes)
[ File body ]
Short header
Tokenized BASIC text
7 x 00H
B. ASCII Text File Format
Long header
10 x OEAH
File name (6 bytes)
t File body ]
Short header
256 x data
Short header
256 x data
Short header
256 x data
Short header
256 x data (includes Control-Z)
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ADVANCED PROGRAMMING GUIDE
C. Machine Language Pile Format
[ File header ]
Long header
10 x 0D0H
File name (6 bytes long)
[ File body 1
Short header
Load start address (1 word)
Load end address (1 word)
Execution start address (1 word)
Machine language program
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ADVANCED PROGRAMMING GUIDE
o Related BIOS Entries
Name:
Function:
Entry:
Returns:
Modifies:
TAPION (OOE1H)
Sets the cassette motor on and reads tape header
None
Carry flag is set if aborted
All
Name:
Function:
Entry:
Returns:
Modifies:
TAPIN (00E4H)
Reads data from tape
None
Data in [ACC], carry flag is set if aborted
All
Name:
Function:
Entry:
Returns:
Modifies:
TAPIOF (00E7H)
Stops reading from tape
None
None
None
Name: TAPOON {OOEAH)
Function: Sets the motor on and writes the tape header
block onto cassette
Entry: [ACC] will contain a non-zero value if a long
header is desired, zero if a short header is
desired
Returns: Carry flag is set if aborted
Modifies: All
Name:
Function:
Entry:
Returns:
Modifies:
TAPOUT (OOEDH)
Writes data to tape
Data to be output in [ACCl
Carry flag is set if aborted
All
Name: TAPOOF (OOFOH)
Function: Stops writing to tape
Entry: None
Returns: None
Modifies: None
[NOTES]
All of the above routines must be entered with the interrupts
disabled.
Because the above pulses are software-generated, all of the
above routines must be called using the same time intervals as
when using BASIC.
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ADVANCED PROGRAMMING GUIDE
2.2.5 MSX Printer Specifications
This document summarizes the requirements for the dot matrix
printers connected to MSX computers.
A. Character Set
The MSX printer should have the same character set that the MSX
computer has. This is a character set with codes of 00 to FE.
The graphics characters (codes between 00H and 1FH) are
represented by two-byte code sequence, preceded by 01H, then
followed by the code itself, added to an offset of 40H.
Example:
To print a character with the code 02H, first send 01H, the
graphic header, then send 42H, the sum of the code (02H) and
the offset (4QH) .
This rule is the same as when sending characters to the screen.
B. Control Codes
The MSX printer supports codes in the format of the NEC PC-8023
printer. The minimum requirements for the MSX printer are as
follows:
0A - Line feed
0C - Form feed (Recommended page length: 66 lines/page)
OD - Carriage return
ESC+"A" - 1/6" line spacing for 8-pin printers, or place a
space between lines.
ESC+"B" - 1/8' line spacing for 8-pin printers, or place no
space between lines.
ESC+"Snnnn" - Dot image print. <nnnn> represents the number
of to follow, in ASCII decimal characters.
If the printer has a line buffer, the following control
character initiates printing of the contents of the line buffer.
OD - Carriage return / Print contents of buffer
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ADVANCED PROGRAMMING GUIDE
C. Non-MSX Printers
MSX-BASIC has a switch in the 5th parameter of the SCREEN
statement. When this is set to 1, MSX-BASIC assumes that the
printer connected to the system has no such capabilities as
described above. In this mode, MSX-BASIC converts those
characters with codes between 00 to 1FH to blanks. The default
value of this switch is 00, meaning that the MSX printer is
connected.
D. Control Functions for the PC-8023 Printer
Control
Code (Hex) Function
8 8 Back space
9 9 Horizontal TAB
10 A Line feed
11 B Vertical TAB
12 C Form feed
13 D Carriage return
14 E Double width
15 F Normal width
27 IB Escape character
29 ID Vertical form control setting start
30 IE Vertical form control setting end
31 IF +chr$(16+n) l<=n<=15 N lines feed
+chr$(n) 2<=n<=6 Vertical tab channel select
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ADVANCED PROGRAMMING GUIDE
ESC + Control
Code Function
1~6 Dot spacing
1 Enhanced print
" Cancel enhanced mode
a Alphanumerics/Hiragana
$ Alphanumerics/Katakana
A
B
T+"nn"
1/6" feed
1/8" feed
n/144" feed
N
P
E
Q
Normal spacing (10 CPI)
Proportional spacing (20 CPI)
Double density dot spacing in graphic print
Elite spacing (12 CPI)
Condensed spacing, 136 characters/line
L+"nnn" Set left margin
S+"nnnn" Bit image print (nnnnsnumber of dots follow)
X Start under line
Y End under line
r Reverse feed
f Forward feed
[
]
Incremental printing.BS erases last character sent
Logical seeking bidirectional print. A chr$(24)
cancels the line sent.
(+"nnn",,,.
)+"nnn",,,.
2
Set horizontal tab
Clear horizontal tab (specified position only)
Clear all the horizontal tab position
179
180
PART C
EXPANDED MSX SYSTEM SOFTWARE
MSX-DOS USER'S GUIDE
3. MSX-DOS
MSX-DOS is a disk operating system for MSX computers. The system
with its compatibility to other versions of MS-DOS will surely
provide you a comfortable environment around. All Microsoft
languages (BASIC Interpreter, BASIC Compiler, FORTRAN, COBOL,
Pascal) will be available under MSX-DOS. Users of MSX-DOS are
assured that their operating system will be the first that
Microsoft will support when any new products or major releases are
announced.
3.1 MSX-DOS User's Guide
3.1.1 System Requirements
The MSX-DOS operating system requires a MSX microcomputer system
with 64k bytes of memory (RAM) and at least one disk drive.
The MSX-DOS disk contains the following files:
File Name Function of File
COMMAND.COM MSX-DOS command processor
MSXDOS.SYS MSX-DOS operating system
3.1.2 Getting Started
Once MSX-DOS has been loaded, the system searches the MSX-DOS
disk for the COMMAND.COM file and loads it into memory. The
OOMMAND.COM file is a program that processes the commands you
enter and then runs the appropriate programs. It is also called
the command processor.
When the command processor is loaded, you will see the following
display on your screen (the underscore represents the cursor):
MSX-DOS Version 1.00
Copyright 1984 by Microsoft
Command version 1.00
Current date is Sun 1-01-1984
Enter new date: _
NOTE
The date format (mm-dd-yy) may
be changed depending on
versions. For example, it is
"yy-mm-dd" in Japanese version.
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MSX-DOS USER'S GUIDE
Any date is acceptable in answer to the new date prompt as long as
it follows the above format. Separators between the numbers can
be hyphens (-) or slashes (/).
After you have answered the new time prompt, the MSX-DOS
A>_
will be displayed.
It tells you that MSX-DOS is ready to accept commands. If you
have inserted the MSX-DOS disk into a drive other than A, the
command processor prompt will reflect that drive (for example, B>).
However, usually you will load MSX-DOS in drive A.
The A in the previous prompt represents the default disk drive.
This means that MSX-DOS will search only the disk in drive A for
any filenames you may enter and will write files to that disk
unless you specify a different drive. You can ask MSX-DOS to
search the disk in drive B by changing the drive designation or by
specifying B: in a command. To change the disk drive designation,
enter the new drive letter followed by a colon. For example:
A> (MSX-DOS prompt)
A>B: (you have typed B: in response to
the prompt)
B> (system responds with B> and drive B
is now the default drive)
The system prompt B> will appear and MSX-DOS will search only the
disk in drive B until you specify a different default drive.
If you have only one disk drive attached to your computer, turn to
3.1.14 'Instructions for Users with Single-Drive Systems', for
important information.
A filename can be from 1 to 8 characters long. The filename
extension can be three or fewer characters. You can type any
filename in small or capital letters and MSX-DOS will translate
these letters into uppercase characters.
In addition to the filename and the filename extension, the
name of your file may include a drive designation. A drive
designation tells MSX-DOS to look on the disk in the designated
drive to find the filename typed.
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MSX-DOS USER'S GUIDE
The following characters are allowed for file names and their
extensions.
A-Z 0-9 $ & #
% ' ( ) - @
¥ ~ j ~ ' i backslash instead of Yen sign
in international versions.)
The term file specification (or filespec) will be used in this
book to indicate the following filename format:
[<drive designation:>]<filename>[<.filename extensions
3.1.3 Wild Cards
Two special characters (called wild cards) can be used in
filenames and extensions: the asterisk (*) and the question mark
(?). These special characters give you greater flexibility when
using filenames in MSX-DOS commands.
o The ? Wild Card
A question mark (?) in a filename or filename extension indicates
that any character can occupy that position. For example, the
MSX-DOS command
DIR TEST?RUN.COM
will list all directory entries on the default drive that have 8
characters, begin with TEST, have any next character, end with the
letters RUN, and have a filename extension of .COM.
o The * Wild Card
An asterisk (*) in a filename or filename extension indicates that
any character can occupy that position or any of the remaining
positions in the filename or extension.
For example:
DIR TEST*. COM
will list all directory entries on the default drive with
filenames that begin with the characters TEST and have an
extension of .COM.
The wild card designation *.* refers to all files on the disk.
Note that this can be very powerful and destructive when used in
MSX-DOS commands. For example, the command DEL *.* deletes all
files on the default drive, regardless of filename or extension.
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MSX-DOS USER'S GUIDE
3.1.4 Illegal File Names
MSX-DOS treats some device names specially, and certain 3-
letter names are reserved for the names of these devices. These
3-letter names cannot be used as filenames or extensions. You
must not name your files any of the following:
AUX Used when referring to input from or output to an
auxiliary device (such as a printer or disk drive).
CON Used when referring to keyboard input or to output to the
terminal console (screen).
LST or
PRN Used when referring to the printer device.
NUL Used when you do not want to create a particular file,
but the command requires an input or output filename.
Even if you add device designations or filename extensions to
these filenames, they remain associated with the devices listed
above. For example, AsCON.XXX still refers to the console and is
not the name of a disk file.
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MSX-DOS USER'S GUIDE
3.1.5 Directories
The directory also contains information on the size of the files,
their locations on the disk, and the dates that they were created
and updated.
3.1.6 Types of MSX-DOS Commands
There are two types of MSX-DOS commands:
Internal commands
External commands
Internal commands are the simplest, most commonly used commands.
You cannot see these commands when you do a directory listing on
your MSX-DOS disk; they are part of the command processor. When
you type these commands, they execute immediately. The following
internal commands are described in 3.2.
BASIC DIR
COPY FORMAT
DATE MODE
DEL (ERASE) PAUSE
REM
REN (RENAME)
TIME
TYPE
VERIFY
External commands reside on disks as program files. They must be
read from disk before they can execute. If the disk containing
the command is not in the drive, MSX-DOS will not be able to find
and execute the command.
Any filename with a filename extension of .COM or .BAT is
considered an external command. For example, programs such as
FILCON.COM and COMP.COM are external commands. Because all
external commands reside on disk, you can create commands and add
them to the system. Programs that you create with most languages
(including assembly language) will be .COM (executable) files.
When you enter an external command, do not include its filename
extension.
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MSX-DOS USER'S GUIDE
3.1.7 Command Options
Options can be included in your MSX-DOS commands to specify
additional information to the system. If you do not include some
options, MSX-DOS provides a default value.
The following is the format of all MSX-DOS commands:
Command [options...]
where:
switches
arguments
filespec
d:
filename
. ext
Switches are options that control MSX-DOS
commands. They are preceded by a slash
(for example, /P).
Provide more information to MSX-DOS commands.
You usually choose between arguments; for
example, ON or OFF.
Refers to an optional drive designation, a
filename, and an optional three letter
filename extension in the following format:
[<d:>]<filename>[<.ext>]
Refers to a disk drive designation.
Refers to any valid name for a disk file,
including an optional filename extension.
The filename option does not refer to a
device or to a disk drive designation.
Refers to an optional filename extension
consisting of a period and 1-3 characters.
When used, filename extensions immediately
follow filenames.
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MSX-DOS USER'S GUIDE
3.1.8 Information Common to All MSX-DOS Commands
The following information applies to all MSX-DOS commands:
o Commands are usually followed by one or more
options.
o Commands and options may be entered in uppercase or
lowercase, or a combination of keys.
o Commands and options must be separated by
delimiters. Because they are easiest, you will
usually use the space and comma as delimiters. For
example:
DEL MYFILE.OLD NEWFILE.TXT
RENAME, THIS FILE THATFILE
You can also use the semicolon (;), the equal
sign (=), or the tab key as delimiters in MSX-DOS
commands.
o Do not separate a file specification with
delimiters, since the colon and the period already
serve as delimiters.
o When instructions say "Strike a key when ready",
you can press any key except <CONTROL-C>.
o You must include the filename extension when
referring to a file that already has a filename
extension.
o You can abort commands when they are running by
pressing <CONTROL-C>.
o Commands take effect only after you have pressed
the <RETURN> key.
o Wild cards (global filename characters) and device
names (for example, PRN or CON) are not allowed in
the names of any commands.
o When commands produce a large amount of output on
the screen, the display will automatically scroll
to the next screen. You can press <CONTROL-S> to
suspend the display. Press any key to resume the
display on the screen.
o MSX-DOS editing and function keys can be used
when entering commands. Refer to 3.1.13 MSX-DOS
Editing and Function Keys, for a complete
description of these keys.
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MSX-DOS USER'S GUIDE
o The prompt from the command processor is the
default drive designation plus a right angle
bracket (>); for example, A>.
o Disk drives will be referred to as source drives
and destination drives. A source drive is the
drive you will be transferring information from. A
destination drive is the drive you will be
transferring information to.
3.1.9 Batch Processing
With MSX-DOS, you can put the command sequence into a special
file called a batch file, and execute the entire sequence simply
by typing the name of the batch file. "Batches" of your commands
in such files are processed as if they were typed at a terminal.
Each batch file must be named with the .BAT extension, and is
executed by typing the filename without its extension.
Two MSX-DOS commands are available for use expressly in batch
files: REM and PAUSE. REM permits you to include remarks and
comments in your batch files without these remarks being executed
as commands. PAUSE prompts you with an optional message and
permits you to either continue or abort the batch process at a
given point.
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MSX-DOS USER'S GUIDE
The following list contains information that you should read
before you execute a batch process with MSX-DOS:
o Do not enter the filename BATCH (unless the name of
the file you want to execute is BATCH.BAT).
o Only the filename should be entered to execute the
batch file. Do not enter the filename extension.
o The commands in the file named <filename>.BAT are
executed.
o If you press <CONTROL-C> while in batch mode, this
prompt appears:
Terminate batch job (Y/N)?
If you press Y, the remainder of the commands in
the batch file are ignored and the system prompt
appears.
If you press N, only the current command ends and
batch processing continues with the next command in
the file.
o if you remove the disk containing a batch file
being executed, MSX-DOS prompts you to insert
it again before the next command can be read.
o The last command in a batch file may be the name of
another batch file. This allows you to call one
batch file from another when the first is finished.
3.1.10 The AUTOEXEC.BAT Pile
When you start MSX-DOS, the command processor searches the MSX-DOS
disk for a file named AUTOEXEC.BAT. The AUTOEXEC.BAT file is a
batch file that is automatically executed each time you start the
system.
If MSX-DOS finds the AUTOEXEC.BAT file, the file is immediately
executed by the command processor and the date prompts are
bypassed.
If MSX-DOS does not find an AUTOEXEC.BAT file when you first load
the MSX-DOS disk, then the date and time prompts will be issued.
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MSX-DOS USER'S GUIDE
3.1.11 How To Create a Batch Pile
If, for example, you wanted to automatically load BASIC and run a
program called MENU each time you started MSX-DOS, you could
create an AUTOEXEC.BAT file as follows:
1. Type:
COPY CON: AUTOEXEC.BAT
This statement tells MSX-DOS to copy the
information from the console (keyboard) into the
AUTOEXEC.BAT file. Note that the AUTOEXEC.BAT
file must be created in the root directory of
your MSX-DOS disk.
2 . Now ty pe:
BASIC MENU
This statement goes into the AUTOEXEC.BAT file.
It tells MSX-DOS to load BASIC and run the MENU
program whenever MSX-DOS is started.
3. Press the <CONTROL-Z> key; then press the <RETURN>
key to put the command BASIC MENU in the
AUTOEXEC.BAT file.
4. The MENU program will now run automatically
whenever you start MSX-DOS.
To run your own BASIC program, enter the name of your program
in place of MENU in the second line of the example. You can enter
any MSX-DOS command or series of commands in the AUTOEXEC.BAT file.
NOTE
Remember that if you use
an AUTOEXEC.BAT file, MSX-DOS
will not prompt you for a
current date unless you
include the DATE command
in the AUTOEXEC.BAT file.
It is strongly recommended
that you include this command
in your AUTOEXEC.BAT file,
since MSX-DOS uses this
information to keep your
directory current.
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MSX-DOS USER'S GUIDE
3.1.12 Replaceable Parameters in .BAT Files.
There may be times when you want to create an application program
and run it with different sets of data. These data may be stored
in various MSX-DOS files.
When used in MSX-DOS commands, a parameter is an option that you
define. With MSX-DOS, you can create a batch (.BAT) file with
dummy (replaceable) parameters. These parameters, named %0-%9,
can be replaced by values supplied when the batch file executes.
For example, when you type the command line COPY CON MYFILE.BAT,
the next lines you type are copied from the console to a file
named MYFILE.BAT on the default drive:
A>COPY CON MYFILE.BAT
COPY %1.MAC %2.MAC
TYPE %2.PRN
TYPE % 0.BAT
Now, press <CONTROL-Z> and then press <RETURN>. MSX-DOS responds
with this message:
1 File(s) copied
A>_
The file MYFILE.BAT, which consists of three commands, now resides
on the disk in the default drive.
The dummy parameters %1 and %2 are replaced sequentially by the
parameters you supply when you execute the file. The dummy
parameter %0 is always replaced by the drive designator, if
specified, and the filename of the batch file (for example,
MYFILE) .
NOTES:
1. Up to 10 dummy parameters (%0—%9) can be specified.
2. If you use the percent sign as part of a filename
within a batch file, you must type it twice. For
example, to specify the file ABC%.COM, you must
type it as ABC%%.COM in the batch file.
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MSX-DOS USER'S GUIDE
To execute the batch file MYFILE.BAT and to specify the parameters
that will replace the dummy parameters/ you must enter the batch
filename (without its extension) followed by the parameters you
want MSX-DOS to substitute for %1, %2, etc.
Remember that the file MYFILE.BAT consists of 3 lines:
COPY %1.MAC %2.MAC
TYPE % 2.PRN
TYPE % 0.BAT
To execute the MYFILE batch process, type:
MYFILE A:PR0G1 B:PR0G2
MYFILE is substituted for %0, A;PROGl for %1, and B:PROG2 for %2.
The result is the same as if you had typed each of the commands
in MYFILE with their parameters, as follows:
COPY A:PR0G1.MAC B:PROG2.MAC
TYPE B:PROG2.PRN
TYPE MYFILE.BAT
The following table illustrates how MSX-DOS replaces each of the
above parameters:
BATCH PARAMETER1 (%0) PARAMETER2 (%1) PARAMETER3 (%2)
FILENAME (MYFILE) (PR0G1) (PROG2)
MYFILE MYFILE.BAT PROG1.MAC PROG2.MAC
PROG2.PRN
Remember that the dummy parameter %0 is always replaced by the
drive designator (if specified) and the filename of the batch file.
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MSX-DOS USER'S GUIDE
3.1.13 MSX-DOS Editing and Function Keys
Special MSX-DOS Editing Keys
Control Character Functions
3.1.13.1 Special MSX-DOS Editing Keys
The special editing keys deserve particular emphasis because they
depart from the way in which most operating systems handle command
input. You do not have to type the same sequences of keys
repeatedly, because the last command line is automatically placed
in a special storage area called the template.
By using the template and the special editing keys, you can take
advantage of the following MSX-DOS features:
o A command line can be instantly repeated by
pressing two keys.
o If you make a mistake in the command line, you can
edit it and retry without having to retype the
entire command line.
o A command line that is similar to a preceding
command line can be edited and executed with a
minimum of typing by pressing special editing keys.
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MSX-DOS USER'S GUIDE
When you type a line to the system call OAH (buffered line input)
and press the RETURN key, the line is returned to the caller of
the system call. This line is copied to the new template. You
can now recall the last line or modify it with MSX-DOS special
editing keys.
The relationship between the command line and the template is
shown in the next figure.
User Input
Command Line < -» Template
i p
COMMAND.COM
Command Line and Template
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MSX-DOS USER’S GUIDE
I NAME I
FUNCTION
COPY1
RIGHT ARROW
~Y (*)
Copies one character from the
template to the new line.
COPYUP
SELECT
"X
Copies all characters from
the template to the new line,
up to the character specified.
COPYALL
DOWN ARROW
Copies all remaining characters
in the template to the new
1 ine.
SKI PI
Skips over (does not copy)
a character in the template.
SKI PUP
Skips over (does not copy)
the characters in the template,
up to the character specified.
VOID
UP ARROW
ESCAPE
Voids the current input. Leaves
the template unchanged.
LEFT ARROW
Deletes the last character
typed.
INSERT
insert
Enters/exits insert mode.
NEWLINE
home
Makes the current line
new template.
Japanese.
‘\ in all other versions.
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MSX-DOS USER'S GUIDE
Example:
If you type the following command
DIR PROG.COM
MSX-DOS displays information about the file PROG.COM on your
screen. The command line is also saved in the template. To
repeat the command, just press two keys: <C0PYALL> and <RETURN>.
The repeated command is displayed on the screen as you type, as
shown below:
<COPYALL>DIR PROG.C0M<RETURN>
Notice that pressing the <C0PYALL> key causes the contents of the
template to be copied to the command line; pressing <RETURN>
causes the command line to be sent to the command processor for
execution.
If you want to display information about a file named PROG.ASM,
you can use the contents of the template and type:
<C0PYUP>C
Typing <C0PYUP>C copies all characters from the template to the
command line, up to but not including "C". MSX-DOS displays:
DIR PROG._
Note that the underline is your cursor. Now type:
.ASM
The result is:
DIR PROG.ASM_
The command line "DIR PROG.ASM" is now in the template and ready
to be sent to the command processor for execution. To do this,
press <RETURN>.
Now assume that you want to execute the following command:
TYPE PROG.ASM
To do this, type:
TYPE<INSERT> <COPYALLXRETURN>
Notice that when you are typing, the characters are entered
directly into the command line and overwrite corresponding
characters in the template. This automatic replacement feature
is turned off when you press the insert key. Thus, the characters
"TYPE" replace the characters "DIR " in the template. To insert
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MSX-DOS USER'S GUIDE
a space between "TYPE" and "PROG.ASM”, you press <INSERT> and then
the space bar. Finally, to copy the rest of the template to the
command line, you press <COPYALL> and then <RETURN>. The command
"TYPE PROG.ASM" will be processed by MSX-DOS, and the template
becomes "TYPE PROG.ASM".
If you had misspelled "TYPE” as "BYTE", a command error would have
occurred. Still, instead of throwing away the whole command, you
could save the misspelled line before you press <RETURN> by
creating a new template with the <NEWLINE> key:
BYTE PROG. ASM<NEWLINE>
You could then edit this erroneous command by typing:
T<COPYl>P<COPYALL>
The <COPYl> key copies a single character from the template to the
command line. The resulting command line is then the command that
you want:
TYPE PROG.ASM
As an alternative, you can use the same template containing BYTE
PROG.ASM and then use the <SKIP1> and <INSERT> keys to achieve the
same result:
<SKIP1XSKIP1><C0PY1XINSERT>YP<C0PYALL>
To illustrate how the command line is affected as you type,
examine the keys typed on the left; their effect on the command
line is shown on the right:
<SKIP1>
<SKIP1>
<C0PY1>
<INSERT>YP
<COPYALL>
_ Skips over 1st template character
_ Skips over 2nd template character
T Copies 3rd template character
TYP Inserts two characters
TYPE PROG.ASM Copies rest of template
Notice that <SKIP1> does not affect the command line. It affects
the template by deleting the first character. Similarly,
<SKIPUP> deletes characters in the template, up to but not
including a given character.
These special editing keys can add to your effectiveness at the
keyboard. The next section describes control character functions
that can also help when you are typing commands.
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MSX-DOS USER'S GUIDE
3.1.13.2 Control Character Functions
A control character
command line. You
<CONTROL-S>. Other
below.
function is a function that affects the
have already learned about <CONTROL-C> and
control character functions are described
Remember that when you type a control character, such as
<CONTROL-C>, you must hold down the control key and then press
the "C" key.
Table of Control Character Functions
Control
Character
Function
<CONTROL-N>
CCONTROL-O
Cancels echoing of output to line printer.
Aborts current command.
<CONTROL-H>
<CONTROL-J>
Removes last character from command line,
and erases character from terminal screen.
Inserts physical end-of-line, but does
not empty command line. Use the <LINE
FEED> key to extend the current logical
line beyond the physical limits of one
terminal screen.
<CONTROL-P>
Echoes terminal output to the line
printer.
<CONTROL-S>
Suspends display of output to terminal
screen. Press any key to resume.
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MSX-DOS USER'S GUIDE
3.1.14 Instructions for Users with Single-drive Systems
On a single-drive system, you enter the commands as you would on a
multi-drive system.
You should think of the single-drive system as having two drives
(drive A and drive B). But instead of A and B representing two
physical drives as on the multi-drive system, the A and B
represent disks.
If you specify drive B when the "drive A disk" was last used, you
are prompted to insert the disk for drive B. For example:
A> COPY COMMAND.COM B:
Insert diskette for drive B:
and strike a key when ready
1 File(s) copied
A>_
If you specify drive A when the "drive B disk" was last used, you
are prompted again to change disks. This time, MSX-DOS prompts
you to insert the "drive A disk."
The same procedure is used if a command is executed from a batch
file. MSX-DOS waits for you to insert the appropriate disk and
to press any key before it continues. You will be prompted to do
this.
NOTE
The letter displayed in the
system prompt represents the
default drive where MSX-DOS
looks to find a file whose
name is entered without a
drive specifier. The letter in
the system prompt does not
represent the last disk used.
For example, assume that A is the default drive. If the last
operation performed was DIR B:, MSX-DOS believes the "drive B
disk" is still in the drive. However, the system prompt is still
A>, because A is still the default drive. If you type DIR,
MSX-DOS prompts you for the "drive A disk" because drive A is
the default drive, and you did not specify another drive in the
DIR command.
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MSX-DOS USER’ S GUIDE
3.1.15 Disk Errors
If a disk error occurs at any time during a command or program,
MSX-DOS retries the operation three times. If the operation
cannot be completed successfully, MSX-DOS returns an error message
in the following format:
<yyy> error <1/0 action> drive x
Abort, Retry, Ignore? _
In this message,<yyy> may be one of the following:
Write protect
Not ready
Disk
The <I/0-action> may be either of the following:
reading
writing
The drive <x> indicates the drive in which the error has occurred.
MSX-DOS waits for you to enter one of the following responses:
A Abort. Terminate the program requesting the disk
read or write.
I Ignore. Ignore the bad sector and pretend the
error did not occur.
R Retry. Repeat the operation. This response is
to be used when the operator has corrected the
error.
Usually, you will want to attempt recovery by entering responses
in this order:
R (to try again)
A (to terminate program and try a new disk)
One other error message might be related to faulty disk read or
write:
Bad FAT
This message means that the copy in memory of one of the
allocation tables has pointers to nonexistent blocks. Possibly
the disk was incorrectly formatted or not formatted before use.
If this error persists, the disk is currently unusable and must be
formatted prior to use.
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MSX-DOS COMMAND GUIDE
3.2 MSX-DOS Command Guide
NOTE
Users of single-drive systems
should refer to 3.1.14 for
the additional procedures
required when executing many
of the following commands.
The following MSX-DOS commands are described here. Note that
synonyms for commands are enclosed in parentheses.
BASIC
Goto MSX-BASIC
COPY
Copies file(s) specified
DATE
Displays and sets date
DEL
Deletes file(s) specified
(ERASE)
DIR
Lists requested directory
entries
FORMAT
Formats a disk to receive
MSX-DOS file
MODE
Sets display screen mode
PAUSE
Pauses for input in a batch file
REM
Displays a comment in a batch file
REN
Renames first file as second file (RENAME)
TIME
Displays and sets time
TYPE
Displays the contents of :
file specified
VERIFY
Sets/Resets verify mode
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MSX-DOS COMMAND GUIDE
BASIC
SYNTAX: BASIC [<filespeO]
PURPOSE: Boots MSX-BASIC
COMMENTS: This command boots the MSX Disk BASIC from the
MSX-DOS.
If a BASIC program file is designated by the
<filespec>, the program is automatically loaded
and run after BASIC starts.
This command changes the slot to make the BASIC
ROM effective. So the memory map is different
between the MSX-DOS and MSX-Disk-BASIC.
Use "CALL SYSTEM" statement to return to the MSX-DOS
from the BASIC.
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MSX-DOS COMMAND GUIDE
SYNTAX:
PURPOSE:
COMMENTS
COPY
COPY <filespec> [<filespec>]
Copies one or more files to another disk. If you
prefer, you can give the copies different names.
This command can also copy files on the same disk.
If the second filespec option is not given, the
copy will be on the default drive and will have
the same name as the original file (first filespec
option). If the first filespec is on the default
drive and the second filespec is not specified,
the COPY will be aborted. (Copying files to
themselves is not allowed.) MSX-DOS will return
the error message:
File cannot be copied onto itself
0 files copied
The second option may take three forms:
1• If the second option is a drive designation
(d:) only, the original file is copied with
the original filename to the designated drive.
2. If the second option is a filename only, the
original file is copied to a file on the default
drive with the filename specified.
3. If the second option is a full filespec, the
original file is copied to a file on the default
drive with the filename specified.
The COPY command also allows file concatenation
(joining) while copying. Concatenation is
accomplished by simply listing any number of files
as options to COPY, separated by "+".
For example,
COPY A. XYZ + B. COM + B:C. TXT BIGFILE. CRP
This command concatenates files named A.XYZ, B.COM,
and B:C.TXT and places them in the file on the
default drive called BIGFILE. CRP.
To combine several files using wild cards into
one file, you could type:
COPY *.LST COMB IN.PRN
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MSX-DOS COMMAND GUIDE
This command would take all files with a filename
extension of .LST and combine them into a file
named COMBIN.PRN.
In the following example, for each file found
matching *.LST, that file is combined with the
corresponding .REF file. The result is a file
with the same filename but with the extension .PRN.
Thus, FILE1.LST will be combined with FILE1.REF
to form FILE1.PRN; then XYZ.LST with XYZ.REF to
form XYZ.PRN; and so on.
COPY *.LST + *.REF *.PRN
The following COPY command combines all files
matching *.LST, then all files matching *.REF,
into one file named COMBIN.PRN:
COPY *.LST + *.REF COMBIN.PRN
Do not enter a concatenation COPY command where
one of the source filenames has the same extension
as the destination. For example, the following
command is an error if ALL.LST already exists:
COPY *.LST ALL.LST
The error would not be detected, however, until
ALL.LST is appended. At this point it could have
already been destroyed.
COPY compares the filename of the input file with
the filename of the destination. If they are the
same, that one input file is skipped, and the error
message "Content of destination lost before copy"
is printed. Further concatenation proceeds
normally. This allows "summing" files, as in this
example:
COPY ALL.LST + *.LST
This command appends all *.LST files, except ALL.LST
itself, to ALL.LST. This command will not produce
an error message and is the correct way to append
files using the COPY command.
Because ASCII files are usually concatenated, this
command interprets a CTRL+Z (1AH) as a end of file
mark in a file. So there is a need of a "/B" switch
to use a physical end of file (length of file
displayed by the DIR command), when binary files
shall be concatenated.
COPY/B A.COM+B.COM
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MSX-DOS COMMAND GUIDE
In this example, the B.COM is appended after the
A.COM, and the destination file name is still A.COM.
Any files can be concatenated by using "/B" switch
for binary file and "/A" for ASCII file. A switch
is effective for the switched file and the after
until a other switch appears.
Whether a CTRL+Z is appended at the end of the
destination file or not is decided by a switch
of the destination file. There is no CTRL+Z in
the source file which is read in effect of ”/A".
Only one CTRL+Z is written when a file is written
in effect of "/A". Therefore more CTRL+Z are
appended as follows.
COPY A.ASM/B B. ASM/A
In this example, "/B" avoids removing CTRL+Z and
"/A" appends a CTRL+Z.
When there is no concatenation, "/A" and "/B"
switchs are valid, and the default file type is
binary. "/A" switch terminates the copy at the
first CTRL+Z.
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MSX-DOS COMMAND GUIDE
SYNTAX:
PURPOSE:
COMMENTS
DATE
DATE [<min>-<dd>-<yy>]
Enter or change the date known to the system. This
date will be recorded in the directory for any
files you create or alter.
You can change the date from your terminal or from
® batch file. (MSX-DOS does not display a prompt
for the date if you use an AUTOEXEC.BAT file, so
you may want to include a DATE command in that
f ile.)
If you type DATE, DATE will respond with the
message:
Current date is <day>-<mm>-<dd>-<yy>
Enter new date:_
Press <RETURN> if you do not want to change the
date shown.
You can also type a particular date after the DATE
command, as in:
DATE 3-9-81
In this case, you do not have to answer the "Enter
new date:" prompt.
The new date must be entered using numerals only;
letters are not permitted. The allowed options
are:
<mm> - 1-12
<dd> «= 1-31
<yy> = 0-79, 80-99 or 1980-2099
The date, month, and year entries may be separated
by hyphens (-), slashes (/) or periods (.). MSX-DOS
is programmed to change months and years correctly,
whether the month has 31, 30, 29, or 28 days.
MSX-DOS handles leap years, too.
<yy> is a two-digit number from 80-99 (the 19 is
assumed), or a two-digit number from 00-79 (the
20 is assumed), or a four-digit number from
1980-2099 (representing year.)
If the options or separators are not valid, DATE
displays the message:
Invalid date
Enter new date:_
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MSX-DOS COMMAND GUIDE
DATE then waits for you to enter a valid date.
NOTE
The date format (mm-dd-yy) may
be changed depending on
versions. For example, it is
"yy-mm-dd" in Japanese version.
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MSX-DOS COMMAND GUIDE
DEL
SYNONYM:
SYNTAX:
PURPOSE:
COMMENTS:
DELETE
ERASE
DEL [filespec]
Deletes all files with the designated filespec.
If the filespec is *.*, the prompt "Are you sure?"
appears. If a "Y" or "y" or <RETURN> is typed
as a response, then all files are deleted as
requested. You can also type ERASE for the DELETE
command.
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MSX-DOS COMMAND GUIDE
DIR
SYNTAX: DIR [filespec] I/P][/W]
PURPOSE: Lists the files in a directory.
COMMENTS: If you just type dir, all directory entries on
the default drive are listed. If only the drive
specification is given (dir d:), all entries on
the disk in the specified drive are listed. If
only a filename is entered with no extension (DIR
filename), then all files with the designated
filename on the disk in the default drive are
listed. If you designate a file specification
(for example, DIR d:filename.ext), all files with
the filename specified on the disk in the drive
specified are listed. In all cases, files are
listed with their size in bytes and with the time
and date of their last modification.
The wild card characters ? and * (question mark
and asterisk) may be used in the filename option.
Note that for your convenience the following DIR
commands are equivalent:
COMMAND
EQUIVALENT
DIR
DIR
*.*
DIR FILENAME
DIR
FILENAME
DIR .EXT
DIR
*. EXT
DIR .
DIR
*
•
Two switches may be specified with DIR. The /P
switch selects Page Mode. With /P, display of
the directory pauses after the screen is filled.
To resume display of output, press any key.
The /W switch selects Wide Display. With /W, only
filenames are displayed, without other file
information. Files are displayed as much as
possible per line.
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MSX-DOS COMMAND GUIDE
SYNTAX:
PURPOSE:
COMMENTS
FORMAT
FORMAT
Formats the disk in the specified drive to accept
MSX-DOS files.
: This command initializes the directory and file
allocation tables. A new disk must be formatted
before use. If a used disk is formatted, all files
in the disk are destroyed.
MSX-DOS issues the following message:
Drive name? (A,B) _
Select a drive name carefully. After you enter
the drive name, the following message is displayed.
Strike a key when ready_
After you insert the new disk in the drive and
press any key on the keyboard.
When the formatting finish , MSX-DOS will issue
a following message.
Format complete
NOTE
The format procedure may be
different with this
description. For example, you
can choose disk format from
single side or double side
with some disk driver. See
your disk driver's manual.
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MSX-DOS COMMAND GUIDE
MODE
SYNTAX: MODE <width>
PURPOSE: Sets the width of the display,
COMMENTS: <width> is the maximum number of characters per
line on display.
<width> must be between 1 and 40. If it is 32
or less, screen mode 1 is selected , else mode
0 is selected.
The default screen mode and width of international
MSX versions are as follows.
I I Default I Default I
I Version I screen I screen I
I I mode i width I
i—--1-—-1—_____--—|
I Japan I 1 l 29 I
l- h- ■{ -H
I USA I I 39 I
— - — — —
I UK I I 1
I-H | I
] DIN 101 I
t--4 I 37 I
I French I t I
i- —i | i
I INT I 1 I
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MSX-DOS COMMAND GUIDE
SYNTAX:
PURPOSE:
COMMENTS
PAUSE
PAUSE [comment]
Suspends execution of the batch file.
During the execution of a batch file, you may need
to change disks or perform some other action. PAUSE
suspends execution until you press any key, except
<CONTROL-C>.
When the command processor encounters PAUSE, it
prints:
Strike a key when ready . . .
If you press <CONTROL-C>, another prompt will be
displayed:
Terminate batch file (Y/N) ?
If you type "Y" in response to this prompt,
execution of the remainder of the batch command
file will be aborted and control will be returned
to the operating system command level. Therefore,
PAUSE can be used to break a batch file into pieces,
allowing you to end the batch command file at an
intermediate point.
The comment is optional and may be entered on the
same line as PAUSE. You may also want to prompt
the user of the batch file with some meaningful
message when the batch file pauses. For example,
you may want to change disks in one of the drives.
An optional prompt message may be given in such
cases. The comment prompt will be displayed before
the "Strike a key" message.
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MSX-DOS COMMAND GUIDE
REM
SYNTAX:
PURPOSE:
COMMENTS:
REM [comment]
Displays remarks which are on the same line as
the REM command in a batch file during execution
of that batch file.
The only separators allowed in the comment are
the space, tab, and comma.
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MSX-DOS COMMAND GUIDE
REN
SYNONYM: RENAME
SYNTAX;
PURPOSE;
COMMENTS;
REN <filespec> <filename>
Changes the name of the first option (filespec)
to the second option (filename).
The first option (filespec) must be given a drive
designation if the disk resides in a drive other
than the default drive. Any drive designation
for the second option (filename) is ignored. The
file will remain on the disk where it currently
resides.
The wild card characters may be used
option. All files matching the first
are renamed. If wild card characters
the second filename, corresponding
positions will not be changed.
in either
filespec
appear in
character
For example, the following command changes the
names of all files with the .LST extension to
similar names with the .PRN extension;
REN *.LST *.PRN
In the next example, REN renames the file ABODE
on drive B to ADOBE;
REN B;ABODE ?D?B?
The file remains on drive B.
An attempt to rename a filespec to a name already
present in the directory will result in the error
message "Rename error"
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MSX-DOS COMMAND GUIDE
SYNTAX:
PURPOSE:
COMMENTS
TIME
TIME [<hh>[:<mm>[:<ss>]1]
Displays and sets the time.
If the TIME command is entered without any arguments,
the following message is displayed:
Current time is <hh>:<mm>:<ss>.<cc>
Enter new time:_
Press the <RETURN> key if you do not want to change
the time shown. A new time may be given as an
option to the TIME command as in:
TIME 8:20
The new time must be entered using numerals only;
letters are not allowed. The allowed options are:
<hh> = 00-24
<mm> = 00-59
< ss > = 00-59
The hour and minute entries must be separated by
colons. You do not have to type the <ss> (seconds)
or <cc> (hundredths of seconds) options.
MSX-DOS uses the time entered as the new time if
the options and separators are valid. If the
options or separators are not valid, MSX-DOS
displays the message:
Invalid time
Enter new time:_
MSX-DOS then waits for you to type a valid time.
NOTE
If your computer does not have
a clock, this command is
nonsense.
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MSX-DOS COMMAND GUIDE
SYNTAX:
PURPOSE:
COMMENTS
TYPE
TYPE <filespec>
Displays the contents of the file on the console
screen.
Use this command to examine a file without modifying
it. (Use dir to find the name of a file.) The
only formatting performed by TYPE is that tabs
are expanded to spaces consistent with tab stops
every eighth column. Note that a display of binary
files causes control characters (such as CONTROL-Z)
to be sent to your computer, including bells, form
feeds, and escape sequences.
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MSX-DOS COMMAND GUIDE
VERIFY
SYNTAX: VERIFY { ON ! OFF }
PURPOSE: Set/reset verify (read after write) mode.
COMMENTS: The VERIFY ON command sets verify mode. Whenever
some data are written into disk, that data are read
from disk and verified. If the verified data is not
correct, "DISK I/O error" occurs.
The VERIFY OFF command resets verify mode.
Default mode is VERIFY OFF.
Writing is more reliable but needs longer time in
verify mode.
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MSX DISK BASIC REFERENCE GUIDE
3.3 MSX Disk BASIC Reference Guide
Microsoft(TM) BASIC is the most extensive implementation of BASIC
available for microprocessors. Microsoft BASIC meets the ANSI
qualifications for BASIC, as set forth in document BSRX3.6 0-197 8.
Each release of Microsoft BASIC is compatible with previous
versions.
MSX(TM) disk BASIC is a release of Microsoft BASIC for the MSX
computer and its flexible disk system.
3.3.1 Commands and Statements
BLOAD
BSAVE
CLOSE
COPY
DSKO
FIELD
FILES and LFILES
FORMAT
GET
INPUT#
KILL
LINE INPUT#
LOAD
LSET and RSET
MAXFILES
MERGE
NAME
OPEN
PRINT# and PRINT# USING
PUT
RUN
SAVE
SYSTEM
VERIFY
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MSX DISK BASIC REFERENCE GUIDE
BLOAD
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
BLOAD "<f ilespec>" { t , R] I [, S] } t , offset]
Loads a machine language program or an array from
disk or cassette tape into memory.
The file name can be omitted only for the file in the
cassette tape, not for the disk.
If no <offset> is specified, the program is loaded
from the address designated by the BSAVE command. If
an <offset> is specified, the program is loaded
from the address added <offset> to the saved address.
Programs to be loaded with the offset must be
relocatable.
The R option automatically runs the program after it
has been loaded.
The S option loads the screen image saved by the
"BSAVE ,S" statement to video RAM.
If no drive name is specified, the program in the
current drive is loaded.
See also "BSAVE,".
BLOAD "MAX2"
Loads file "MAX2" into memory.
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MSX DISK BASIC REFERENCE GUIDE
BSAVE
SYNTAX:
PURPOSE:
COMMENTS:
BSAVE "<file spec>" f <start address>,<end address>
U,<execute address>]I[,S]}
Saves the machine language program
memory on disk or cassette tape.
currently
in
The program from <start address> to <end address> in
memory is saved on disk or cassette tape.
If no drive name is specified, the program is saved
on the current drive.
<start address> defines the default execution address.
The S option saves the content of video RAM to the
r lie.
See also "BLOAD, ".
EXAMPLE: BSAVE "TIMER", &HCOOO, &HCFFF
Saves the program currently in memory from &HC000
to &HCFFF on current drive under filename "TIMER".
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HSX DISK BASIC REFERENCE GUIDE
CLOSE
SYNTAX: CLOSE [[#]<file number>[,[#]<file number...>]]
PURPOSE:
COMMENTS:
EXAMPLE:
Concludes I/O to a disk file.
<file number> is the number under which the file was
OPENed. A CLOSE with no arguments closes all open
files.
The association between a particular file and file
number terminates upon execution of a CLOSE statement.
The file may then be reOPENed using the same or a
different file number; likewise/ that file number
may now be reused to OPEN any file.
A CLOSE for a sequential output file writes the final
buffer of output.
The END, CLEAR statements and the NEW command always
CLOSE all disk files automatically.
(STOP does not close disk files.)
CLOSE #1
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MSX DISK BASIC REFERENCE GUIDE
COPY
SYNTAX:
PURPOSE:
COMMENTS:
COPY "<file spec>" TO "<file spec>"
Copies one or more files to another disk. If you
prefer, you can give the copies different names.
This command can also copy files on the same disk.
The second option may take three forms:
1. If the second option is a drive designation
(d:) only, the original file is copied with
the original filename to the designated drive.
2. If the second option is a filename only, the
original file is copied to a file on the default
drive with the filename specified.
3. If the second option is a full filespec, the
original file is copied to a file on the default
drive with the filename specified.
On a single-drive system, you enter the commands as
you would on a multi-drive system.
If you specify drive B when the "drive A disk" was
last used, you are prompted to insert the disk for
drive B. For example:
COPY "A:TEST.ASC” TO "B:"
After the file is loaded from "drive A disk" to
memory, you are prompted as follows.
Insert diskette for drive B:
and strike a key when ready
You remove "A disk" and insert "B disk". Then strike
any key (except CONTROL-STOP). If the file is small,
copy is completed.
But, if the file is big, you must exchange two disks
following the prompted instructions until copy is
completed. Because parts of the file are loaded and
saved one after another.
If you specify drive A when the "drive B disk” was
last used, you are prompted again to change disks.
This time, BASIC prompts you to insert the "drive A
disk". See also section 3.1.14.
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MSX DISK BASIC REFERENCE GUIDE
DSKO
SYNTAX:
COMMENTS:
NOTE:
DSKO <drive_number>,<1 ogical_sector__number>
Writes to the specified sector from memory pointed
to by the content of (0F351H,0F352H) .
<drive_number> is 0 for default drive, 1 for drive A,
2 for drive B, and so on.
<logical_sector_number> is a 0 based number. No check
for the valid sector number is made.
This memory area is destroyed when any disk
statements (ex. FILES, OPEN, CLOSE, PRINT#, etc.) are
executed.
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MSX DISK BASIC REFERENCE GUIDE
FIELD
SYNTAX:
PURPOSE:
COMMENTS:
NOTE:
EXAMPLE 1:
FIELD [#]<file number>,<field width>
AS <string variable>...
Allocates space for variables in a random file
buffer.
Before a GET statement or PUT statement can be
executed, a FIELD statement must be executed to
format the random file buffer.
<file number> is the number under which the file was
OPENed. <field width> is the number of characters
to be allocated to <string variable>.
For example,
FIELD 1,20 AS N$,10 AS IDS,40 AS ADDS
allocates the first 20 positions (bytes) in the
random file buffer to the string variable N$, the
next 10 positions to IDS, and the next 40 positions
to ADDS. FIELD does NOT place any data in the
random file buffer. (See "LSET/RSET,", and "GET,".)
The total number of bytes allocated in a FIELD
statement must not exceed the record length that was
specified when the file was OPENed. Otherwise, a
"Field overflow" error occurs.
(The default record length is 256 bytes.)
Any number of FIELD statements may be executed for
the same file. All FIELD statements that have been
executed will remain in effect at the same time.
Do not use a FIELDed variable name in an INPUT or
LET statement. Once a variable name is FIELDed,
it points to the correct place in the random file
buffer. If a subsequent INPUT or LET statement with
that variable name is executed, the variable’s
pointer is moved to string space.
10 OPEN "ArPHONELST" AS #1 LEN=35
15 FIELD #1,2 AS RECNBR$,33 AS DUMMY$
20 FIELD #1,25 AS NAMES,10 AS PHONENBRS
25 GET #1
30 TOTAL=CVI (RECNBR) $
35 FOR 1=2 TO TOTAL
40 GET #1, I
45 PRINT NAMES, PHONENBR5
50 NEXT I
Illustrates a multiple defined FIELD statement. In
statement 15, the 35 byte field is defined for the
first record to keep track of the number of records
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MSX DISK BASIC REFERENCE GUIDE
EXAMPLE 2:
EXAMPLE 3:
in the file. In the next loop of statements (35-50),
statement 20 defines the field for individual names
and phone numbers.
10 FOR LOOP%=0 TO 7
20 FIELD #1,(LOOP%*16) AS OFFSETS,16 AS A$(LOOP%)
30 NEXT LOOP%
Shows the construction of a FIELD statement using
an array of elements of equal size. The result is
equivalent to the single declaration:
FIELD #1,16 AS A?(0),16 AS A$(l),...,16 AS A$(6)
,16 AS A$(7)
10 DIM SIZ E% (NUMB%>: REM ARRAY OF FIELD SIZES
20 FOR LOOP%=0 TO NUMB%:READ SIZE%(LOOP%): NEXT LOOP%
30 DATA 9,10,12,21,41
•
120 DIM A$(NUMB%): REM ARRAY OF FIELDED VARIABLES
130 OFFSET%=0
140 FOR LOOP%=0 TO NUMB%
150 FIELD #l,OFFSET% AS OFFSETS,SIZE%(LOOP%)
AS A$(LOOP%)
16 0 OFFSET%=OFFSET%+SIZ E%(LOOP%)
170 NEXT LOOP%
Creates a field in the same manner as Example 2.
However, the element size varies with each element.
The equivalent declaration is:
FIELD #1,SIZE%(0) AS A$(0) ,SIZE%(1) AS A$(l),...
SIZ E%(NUMB%) AS A$(NUMB%)
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MSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE:
COMMENTS
EXAMPLE:
FILES and LFILES
FILES I"<file spec>"]
LFILES [”<fiie spec>"]
Displays or prints file names of disk files.
: The file names designated by the <file spec> are
displayed. If the designated file does not exists.
File not found" error is occurs.
If no <file spec> is specified, all file names in the
current drive are displayed.
There can be question mark (?) in the file name to
substitute for a character in the file name or
extension. And, there can be asterisk (*) to
substitute for any file name or extension.
If the drive name is designated, the file names in
that drive is displayed, else in current drive.
The LFILES command outputs file names not to display
but to printer.
FILES "B:BAS"
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MSX DISK BASIC REFERENCE GUIDE
FORMAT
SYNTAX:
PURPOSE:
COMMENTS:
NOTE:
CALL FORMAT
or
_FORMAT
Initializes a disk.
Menu is displayed as follows.
Drive name? (A,B) _
Select a drive name carefully. After you enter
the drive name, the following message is
displayed.
Strike a key when ready_
After you insert the new disk in the drive and
press any key on the keyboard.
When the formatting is finished, BASIC will issue
the following message.
Format complete
If a used disk is formatted, all files in that
disk is destroyed.
New disks must be formatted before use.
The format procedure may be different with this
description. For example, you can choose disk
format from single side or double side with some
disk driver. See your disk driver's manual.
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MSX DISK BASIC REFERENCE GUIDE
GET
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
NOTE:
GET [#]<file number>[,<record number>]
Reads a record from a random disk file into a random
buffer.
<file number> is the number under which the file was
OPENed. If <record number> is omitted, the next
record (after the last GET) is read into the buffer.
The largest possible record number is 4,294,967,295.
10 OPEN "SAMPLE.DAT" AS #1
20 FIELD #1, 2 AS A$, 10 AS B$
30 FOR I%=1 TO 10
40 GET #1, 1%
50 PRINT CVI (A$) ; B$
60 NEXT
7 0 CLOSE #1
80 END
After an execution of a GET statement, INPUT# and
LINE INPUT# may be executed to read characters from
the random file buffer.
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MSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE:
COMMENTS
EXAMPLE:
INPUT#
INPUT#<file number>,<variable list>
Reads data items from a sequential disk file and
assigns them to program variables.
: <file number> is the number used when the file was
OPENed for input. <variable list> contains the
variable names that will be assigned to the items in
the file. (The variable type must match the type
specified by the variable name.)
With INPUT#, no question mark is printed, as with
INPUT.
The data items in the file should appear just as they
would if data were being typed in response to an
INPUT statement. With numeric values, leading
spaces, carriage returns, and line feeds are ignored.
The first character encountered that is not a space,
carriage return, or line feed is assumed to be the
start of a number. The number terminates on a space,
carriage return, line feed, or comma.
If MSX BASIC is scanning the sequential data file for
a string item, leading spaces, carriage returns, and
line feeds are also ignored. The first character
encountered that is not a space, carriage return, or
line feed is assumed to be the start of a string
If this first character is a quotation mark
( ), the string item will consist of all characters
read between the first quotation mark and the second.
Thus, a quoted string may not contain a quotation
mark as a character. If the first character of the
string is not a quotation mark, the string is an
unquoted string, and will terminate on a comma,
a carriage return, or a line feed (or after 255
characters have been read). If end-of-file is reached
when a numeric or string item is being INPUT, the
item is terminated.
10 OPEN "SAMPLE2.DAT" FOR INPUT AS #1
20 INPUT #1, A$
30 PRINT A$
40 IF EOF(l)=0 THEN 20
50 CLOSE #1
6 0 END
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MSX DISK BASIC REFERENCE GUIDE
KILL
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
KILL "<file spec>"
Deletes a file from disk.
If a KILL statement is given for a file that is
currently OPEN, a "File already open" error occurs.
KILL is used for all types of disk files: program
files, random data files, and sequential data files.
200 KILL "DATA1.DAT"
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MSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE:
COMMENTS
EXAMPLE:
LINE INPUT#
LINE lNPUT#<file number>,<string variable>
Reads an entire line (up to 254 characters), without
delimiters, from a sequential disk data file to a
string variable.
: <file number> is the number under which the file was
OPENed. <string variable> is the variable name to
which the line will be assigned. LINE INPUT# reads
all characters in the sequential file up to a
carriage return. It then skips over the carriage
return/line feed sequence. The next LINE INPUT# reads
all characters up to the next carriage return.
(If a line feed/carriage return sequence is
encountered, it is understood as a string ending with
a line feed character.)
LINE INPUT# is especially useful if each line of a
data file has been broken into fields, or if an
MSX BASIC program saved in ASCII format is being read
as data by another program. (See "SAVE,".)
10 OPEN "LIST" FOR OUTPUT AS #1
20 LINE INPUT "CUSTOMER INFORMATION? ";C$
30 PRINT #1, C?
40 CLOSE 1
50 OPEN "LIST" FOR INPUT AS #1
60 LINE INPUT #1, C$
70 PRINT C$
80 CLOSE 1
RUN
CUSTOMER INFORMATION? LINDA JONES 234,4 MEMPHIS
LINDA JONES 23 4,4 MEMPHIS
Ok
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MSX DISK BASIC REFERENCE GUIDE
LOAD
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
LOAD <f ilename>[ ,R]
Loads a file from disk into memory.
<filename> is the name that was used when the file
was SAVEd.
The R option automatically runs the program after
it has been loaded.
LOAD closes all open files and deletes all variables
and program lines currently residing in memory before
it loads the designated program. However, if the R
option is used with LOAD, the program is RUN after it
is LOADed, and all open data files are kept open.
Thus, LOAD with the R option may be used to chain
several programs (or segments of the same program).
Information may be passed between the programs using
their disk data files.
Until the designated file is found and started
being loaded, the program in memory is kept.
LOAD "STRTRK",R
LOAD ”B:MYPROG”
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MSX DISK BASIC REFERENCE GUIDE
LSET and RSET
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
NOTE:
LSET <string vaciable>=<string expression>
RSET <string variable>=<string expression>
Moves data from memory to a random file buffer
(in preparation for a PUT statement).
If <string expression> requires fewer bytes than were
FlELDed to <string variable>, LSET left-justifies
the string in the field, and RSET right-justifies the
string. (Spaces are used to pad the extra positions.)
If the string is too long for the field, characters
are dropped from the right. Numeric values must be
converted to strings before they are LSET or RSET.
(See "MKI$, MKS$, MKD$,",)
150 LSET A$=MKS$(AMT)
160 LSET D$=DESC($)
LSET or RSET may also be used with a nonfielded
string variable to left-justify or right-justify a
string in a given field. For example, the program
lines
110 A$ = SPACE $ (20)
120 RSET A$=N$
right-justify the string N$ in a 20-character field.
This can be very handy for formatting printed output.
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MSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE:
COMMENTS
MAXFILES
MAXFILES=<expression>
Specifies the maximum number of files opened at a
time.
: <expression> can be in the range of 0 to 15. When
'MAXFILES=0' is executed, only SAVE and LOAD can be
performed.
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MSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE:
COMMENTS
EXAMPLE:
MERGE
MERGE <filename>
Merges a specified disk file into the program
currently in memory.
<filename> is the name used when the file was SAVEd.
The file must have been SAVEd in ASCII format. (If
not, a "Bad file mode" error occurs.)
If any lines in the disk file have the same line
numbers as lines in the program in memory, the lines
from the file on disk will replace the corresponding
lines in memory. (MERGEing may be thought of as
"inserting" the program lines on disk into the
program in memory.)
MSX BASIC always returns to command level after
executing a MERGE command.
MERGE "NUMBRS"
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MSX DISK BASIC REFERENCE GUIDE
NAME
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
NAME <old filespec> AS <new filename>
Changes the name of a disk file.
Cold filespec> must exist and Cnew filename> must
not exist; otherwise, an error will result. After
a NAME command, the file exists on the same disk, in
the same area of disk space, with the new name.
If no drive name is specified, the current drive is
selected.
NAME "ACCTS" AS "LEDGER"
In this example, the file that was formerly named
ACCTS will now be named LEDGER.
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MSX DISK BASIC REFERENCE GUIDE
OPEN
SYNTAX:
PURPOSE:
COMMENTS:
NOTE:
EXAMPLE:
OPEN "<filespec>" [FOR<mode>] AS I#] <file number>
[LEN=<reclen>]
Allows I/O to a disk file.
A disk file must be OPENed before any disk I/O
operation can be performed on that file. OPEN
allocates a buffer for I/O to the file and determines
the mode of access that will be used with the buffer.
<mode> is one of the following:
FOR OUTPUT Specifies sequential output mode.
FOR INPUT Specifies sequential input mode.
FOR APPEND Specifies sequential append mode after
end of an existent file.
default Specifies random input/output mode.
<file number> is an integer expression whose value is
between one and the maximum number of files specified
in a MAXFILES statement.The number is then associated
with the file as long as it is OPEN and is used to
refer to other disk I/O statements to the file.
<filename> is a string expression containing a name
that conforms to your operating system's rules for
disk filenames.
<reclen> is an integer expression which, if included,
sets the record length for random files. The default
record length is 256 bytes. The largest possible
record length is 256. The smallest is 1.
If sequential input or append mode is used for non¬
existent file, "File not found" error occurs. If
sequential output mode is used for existent file,
the old file is deleted.
A file can be OPENed for sequential input or random
access on more than one file number at a time. A file
may be OPENed for output, however, on only one file
number at a time.
10 OPEN "INVEN” FOR INPUT AS #1
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MSX DISK BASIC REFERENCE GUIDE
PRINT# and PRINT# USING
SYNTAX: PRINT#<file number>,[USING <string exp>;]
<list of expressions>
PURPOSE: Writes data to a sequential disk file.
COMMENTS: <file number> is the number used when the file was
OPENed for output. <string exp> consists of
formatting characters as described in "PRINT USING."
The expressions in <list of expressions> are the
numeric and/or string expressions that will be
written to the file.
PRINT# does not compress data on the disk. An image
of the data is written to the disk/ just as it would
be displayed on the terminal screen with a PRINT
statement. For this reason, care should be taken to
delimit the data on the disk, so that it will be
input correctly from the disk.
In the list of expressions, numeric expressions
should be delimited by semicolons. For example:
PRINTll,A;B;C;X;Y;Z
(If commas are used as delimiters, the extra blanks
that are inserted between print fields will also be
written to the disk.)
String expressions must be separated by semicolons
in the list. To format the string expressions
correctly on the disk, use explicit delimiters in the
list of expressions.
For example, let A$="CAMERA" and B$="93604-1".
The statement
PRINT#1,A$;B$
would write CAMERA93604-1 to the disk. Because there
are no delimiters, this could not be input as two
separate strings. To correct the problem, insert
explicit delimiters into the PRINT# statement as
follows:
PRINT#1,A$j",";B?
The image written to disk is
CAMERA, 93 6 04-1
which can be read back into two string variables.
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MSX DISK BASIC REFERENCE GUIDE
If the strings themselves contain commas, semicolons,
significant leading blanks, carriage returns, or line
feeds, write them to disk surrounded by explicit
quotation marks, CHR$(34).
For example, let A$="CAMERA, AUTOMATIC" and
B $=" 93604-1". The statement
PRINT#1,A$;B $
would write the following image to disk:
CAMERA, AUTOMATIC 93604-1
And the statement
INPUT#1,A$,B$
would input "CAMERA" to A$ and "AUTOMATIC 93604-1"
to B$. To separate these strings properly on the
disk, write double quotation marks to the disk image
using CHR$(34). The statement
PRINT#1,CHR$(34);A$;CHR$(34);CHRS(34);B$;CHR$<34)
writes the following image to disk:
"CAMERA, AUTOMATIC"" 93604-1"
And the statement
INPUT#1,A$,B$
would input "CAMERA, AUTOMATIC" to A$ and
" 93604-1" to B$.
The PRINT# statement may also be used with the USING
option to control the format of the disk file. For
example:
PRINT#1,USING”¥¥###.##,";J;KjL
(Japanase. Refer to 5.4 for other versions.)
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MSX DISK BASIC REFERENCE GUIDE
PUT
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
NOTE:
PUT [*] <f ile number>[,<record number>]
Writes a record from a random buffer to a random disk
file.
<file number> is the number under which the file
was OPENed. if Crecord number> is omitted, the
record will assume the next available record number
(after the last PUT)♦ The largest possible record
number is 4,294,967,295. The smallest record number
is 1.
10 OPEN "SAMPLE.DAT" AS #1
20 FIELD #1, 2 AS A$, 10 AS B$
30 FOR I%=1 TO 10
40 INPUT N%, S$
50 LSET A$=MKI${N%)
60 LSET B$=S$
7 0 PUT #1, 1%
80 NEXT
90 CLOSE #1
100 END
LSET or RSET statement must be used to put characters
in the random file buffer before executinq a PUT
statement.
Any attempt to read or write past the end of the
buffer causes a "Field overflow" error.
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MSX DISK BASIC REFERENCE GUIDE
RUN
SYNTAX:
PURPOSE:
COMMENTS:
EXAMPLE:
RUN <filename>[,R]
Loads a file from disk into memory and runs it.
<filename> is the name used when the file was SAVEd.
RUN closes all open files and deletes the current
contents of memory before loading the designated
program. However, with the "R" option, all data
files remain OPEN.
RUN "NEWFIL", R
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MSX DISK BASIC REFERENCE GUIDE
SAVE
SYNTAX:
PURPOSE:
COMMENTS:
NOTE:
EXAMPLE:
SAVE <filespec>[,A]
Saves a program file on disk.
<filespec> is a quoted string that conforms to
MSX-DOS's requirements for filenames. If <filespec>
already exists, the file will be written over.
Use the A option to save the file in ASCII format.
Otherwise, MSX BASIC saves the file in a compressed
binary format. ASCII format takes more space on the
disk, but some disk access requires that files be in
ASCII format. For instance, the MERGE command
requires an ASCII format file, and some operating
system commands such as LIST may require an ASCII
format file.
"CSAVE" and "SAVE" are used for binary and ASCII
save of cassete tape file. But "SAVE" and
SAVE ... ,a" are used for that cases of disk file.
SAVE "COM2", A
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MSX DISK BASIC REFERENCE GUIDE
SYSTEM
SYNTAX: CALL SYSTEM
or
_SYSTEM
PURPOSE: Exits from disk BASIC and returns to MSX-DOS.
COMMENTS: This command is valid only when BASIC has been
booted from MSX-DOS.
By this command all files are closed and the program
and the data in memory are destroyed.
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MSX DISK BASIC REFERENCE GUIDE
VERIFY
SYNTAX:
PURPOSE:
COMMENTS:
NOTE:
CALL VERIFY { ON I OFF }
or
_VERIFY { ON I OFF }
Sets/resets verify (read after write) mode.
The VERIFY ON command sets verify mode. Whenever
some data are written into disk, that data are read
from disk and verified. If the verified data is not
correct, "DISK I/O error" occurs.
The VERIFY OFF command resets verify mode.
Default mode is VERIFY OFF.
Writing is more reliable but needs longer time in
verify mode.
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MSX DISK BASIC REFERENCE GUIDE
3.3.2 Functions
CVI, CVS/ CVD
DSKF
DSKI ?
EOF
INPUT?
LOC
LOF
MKI$,MKS $/MKD $
VARPTR
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MSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE:
EXAMPLE:
SYNTAX:
PURPOSE
EXAMPLE
CVI, CVS, CVD
CVI(<2-byte string>)
CVS(<4-byte string>)
CVD(<8-byte string>)
To convert string values to numeric values. Numeric
values that are read in from a random disk file must
be converted from strings back into numbers. CVI
converts a 2-byte string to an integer. CVS converts
a 4-byte string to a single precision number. CVD
converts an 8-byte string to a double-precision
number.
70 FIELD #1,4 AS NS, 12 AS B$, ...
80 GET #1
90 Y=CVS(N$)
See also "MKIS, MKS$, MKD$, ".
DSKF
DSKF(<drive number>)
To know free area size of specified disk by K byte.
The drive number corresponds to the drive name as
follows.
0 default drive
1 drive A:
2 drive B:
and so on
PRINT DSKF(l)
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MSX DISK BASIC REFERENCE GUIDE
DSKI5
SYNTAX:
PURPOSE:
NOTE:
EOF
SYNTAX:
PURPOSE:
EXAMPL E:
DSKI $ (<drive_number >,<logical_sector_number >)
To read the specified sector to memory pointed to
by the content of (0F351H,0F352E) .
<drive_number> is 0 for default drive, 1 for drive A,
2 for drive B, and so on.
<logical_sector_number> is a 0 based number. No check
for the valid sector number is made.
This memory area is destroyed when any disk
statements (ex. FILES, OPEN, CLOSE, PRINT#, etc.)
are executed.
EOFKfile number>)
To know if the end of a sequential file has been
reached. Returns -1 (true) if so. Use EOF to test
for end-of-file while INPUTting, to avoid "Input past
end" errors.
The file specified by the file number must be opened
as sequential input mode.
10 OPEN "DATA" FOR INPUT AS #1
20 C=0
30 IF EOF (1) THEN 100
40 INPUT #1, M (C)
50 C=C+1 :GOTO 30
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MSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE:
EXAMPLE:
SYNTAX:
PURPOSE
EXAMPLE
INPUT?
INPUT?(X[, [#]Y] )
To read data from the terminal or from file number Y.
Returns a string of X characters, If the terminal
is used for input, no characters will be echoed. All
control characters are passed through except Control-
STOP, which is used to interrupt the execution of
the INPUT? function.
5 'LIST THE CONTENTS OF A SEQUENTIAL FILE IN
HEXADECIMAL
10 OPEN "DATA" FOR INPUT AS #1
20 IF EOF(1) THEN 50
30 PRINT HEX? (ASC (INPUT$(1,#1) ) ) ;
40 GOTO 20
50 PRINT
60 END
LOC
LOC(<file number>)
where <file number> is the number under which the
file was OPENed.
With random disk files, LOC returns the record number
just read or written from a GET or PUT statement.
If the file was opened but no disk I/O has been
performed yet, LOC returns a 0. With sequential
files, LOC returns the number of records read from
or written to the file since it was OPENed. When no
record is read from the sequential input file since
it was opened, LOC returns 1, because SYSTEM has read
the first sector.
200 IF LOC(1)>50 THEN STOP
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MSX DISK BASIC REFERENCE GUIDE
LOF
SYNTAX:
PURPOSE:
EXAMPLE:
MKI $ ,
SYNTAX:
PURPOSE:
EXAMPLE:
LOF(<file number>)
LOF returns the size of the specified file by byte.
IF NUM%>LOF (1) THEN PRINT "INVALID"
MKS $ , MKD$
MKI $ Kinteger expression>)
MKS$(<single precision expressions
MKD$(<double precision expression>)
To convert numeric values to string values. Any
numeric value that is placed in a random file buffer
with an LSET or RSET statement must be converted to a
string. MKI$ converts an integer to a 2-byte string.
MKS $ converts a single precision number to a 4-byte
string. MKD$ converts a double precision number to
an 8-byte string.
90 AMT=(K+T)
100 FIELD #1,8 AS D$,20 AS N$
110 LSET D5=MKS$(AMT)
120 LSET N$=A$
130 PUT #1
See also "CVI, CVS, CVD,".
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HSX DISK BASIC REFERENCE GUIDE
SYNTAX:
PURPOSE
EXAMPLE
VARPTR
VARPTR(#<f ile number >)
VARPTR returns the address of the file control block
assigned to <file number>.
100 X=USR(VARPTR(#1))
251
MSX DISK BASIC REFERENCE GUIDE
3.3.3 Error Codes and Error Messages
Code Number Disk Errors Message
50 Field overflow
A FIELD statement is attempting to allocate
more bytes than were specified for the record
length of a random file.
51 Internal error
An internal malfunction has occurred in
MSX BASIC. Report to Microsoft the
conditions under which the message appeared.
52 Bad file number
A statement or command references a file with
a file number that is not OPEN or is out of
the range of file numbers specified at
initial ization.
53 File not found
A LOAD, KILL, or OPEN statement references a
file that does not exist on the current disk.
54 File already open
A sequential output mode OPEN statement is
issued for a file that is already open; or a
KILL statement is given for a file that is
open.
55 Input past end
An INPUT statement is executed after all the
data in the file has been INPUT, or for a
null (empty) file. To avoid this error, use
the EOF function to detect the end-of-file.
56 Bad file name
An illegal form is used for the filename with
a LOAD, SAVE, KILL, or OPEN statement (e.g.,
a filename with too many characters).
57 Direct statement in file
A direct statement is encountered while
LOADing an ASCII-format file. The LOAD is
terminated.
252
MSX DISK BASIC REFERENCE GUIDE
5 8 Sequential I/O only
A GET or PUT statement is used on a sequential
file.
59 File not open
An input or output statement is executed on a
not opened file.
60 Bad allocation table
The disk is not initialized.
61 Bad file mode
An attempt is made to use PUT, GET, or LOF
with a sequential file, to LOAD a random
file, or to execute an OPEN statement with a
file mode other than "FOR INPUT", "FOR OUTPUT"
, "FOR APPEND" or default (random).
62 Bad drive name
A invalid drive name is specified.
64 File still open
The file is not closed.
65 File already exists
The filename specified in a NAME statement is
identical to a filename already in use on the
disk.
66 Disk full
All disk storage space is in use.
67 Too many files
An attempt is made to create a new file
(using SAVE or OPEN) when all 255 directory
entries are full.
68 Disk write protected
A PUT or PRINT# statement is executed on
a write protected disk.
69 Disk I/O error
An I/O error occurred on a disk I/O
253
MSX DISK BASIC REFERENCE GUIDE
operation. It is a fatal error; i.e., the
operating system cannot recover from the
error.
70 Disk offline
There is no disk in the specified drive.
71 Rename across disk
A RENAME statement is executed, across one
drive to another.
254
MSX-DOS BOOT PROCEDURE
3.4 MSX-DOS Boot Procedure
1) Boot Procedure
When all the buffers for the disk system are successfully
allocated, the disk ROM checks the contents of address OFEDAH
to see if a ROM cartridge has set the hook (H.STKE) to gain
control of the disk system. If the contents is not a 'RET'
instruction (0C9H), the disk ROM sets up environments for disk
BASIC and jumps to this hook.
The disk ROM next checks if there is an existing cartridge
which has a TEXT entry in the cartridge header. If such a
cartridge is found, the disk ROM sets up environments for disk
BASIC and executes the BASIC program from the cartridge.
Next, the first sector of a first track (logical sector number
0) is read and transferred to 0C000H to OCOFFH. If this read
routine fails because of a drive not ready, a read error, or
if the first byte of the boot sector is not 0EBH nor 0E9H,
disk BASIC starts up.
Next, address 0C01EH is called with the carry flag set. This
routine is provided so as to make game or other application
programs take control of the disk system. The standard boot
sector (provided) will just execute a 'RET' instruction if the
carry flag is reset.
The ROM program next does a non-destructive memory check. If
a 64K~byte RAM is not available, the program transfers control
to disk BASIC.
Next the environments for MSXDOS are set up, and the routine
jumps to 0C01EH with the carry flag set. Our standard boot
sector loads MSXDOS.SYS at 100H and jumps to it. If MSXDOS.SYS
not present, disk BASIC is invoked.
MSXDOS. SYS loads COMMAND.COM at 100H and jumps to it. If
COMMAND.COM is not present, the routine prompts the user to
insert a diskette with COMMAND.COM in it.
2) AUTOEXEC.BAT
When MSXDOS is first booted, it searches for a file named
AUTOEXEC.BAT and executes it as a batch file.
3) AUTOEXEC. BAS
When MSX disk BASIC is first invoked, it looks for a file
named AUTOEXEC.BAS and executes it as a BASIC program.
255
MSX—DOS AND DISK BASIC DISK DRIVER
3.5 MSX-DOS and MSX Disk BASIC Disk Driver
The following values must be defined and declared as PUBLIC by
the person or organization doing the interfacing.
MYSIZ E
Byte size of the work area used by the driver.
SECLEN
The maximum sector size for the media supported by the
driver.
DEFDPB
The base address of the DPB (which consists of 18 bytes)
for the media having the largest value for FATSIZ*SECSIZ.
The following subroutines must be provided and declared as PUBLIC
by the person or organization doing the interfacing.
INIHRD
DRIVES
INIENV
DSKIO
DSKCHG
GETDPB
CHOICE
DSKFMT
OEMSTATEMENT
Initialize hardware
Return number of drives in system
Initialize work area
Read/Write to disk
Get disk change status
Get drive parameter block
Return character string for disk formatting
Format disk
(Entry point for use in system expansion)
The following
is a detailed description the above routines.
INIHRD
Inputs:
None
Outputs:
None
Registers:
AF, BC, DE, HL, IX, IY may be affected.
This routine initializes the hardware as soon as the
control passes to the cartridge. Note that no work area
is assigned when this routine is initiated.
256
MSX-DOS AND DISK BASIC DISK DRIVER
DRIVES
Inputs:
IF! =
The zero
' flag
is reset
in case one
physical
drives.
drive
must act
as two logical
Outputs:
[L] =
Registers:
Number of
drives
connected
F, HL,
IX, IY may
be affected.
Before any other processing can be done, the number of
drives connected to the cartridge must be counted.
If more than one drive is detected, or if the zero flag
passed from the calling routine is set, the number of
drives is returned (unmodified).
If only one drive has been detected and the zero flag
passed is reset, a '2' must be returned as the number of
drives, and the DSKIO and DSKFMT routines must logically
support two drives. Use the PROMPT routine (described
below) when switching drives.
When this routine is entered, the work area for the driver
is already allocated.
INIENV
Inputs:
None
Outputs:
None
Registers:
AF, BC, DE, HL, IX, IY may be affected.
This entry initializes the work area (environment).
INIHRD, DRIVES and INIENV are called only
once during initialization, in the above
order.
257
MSX-DOS AND DISK BASIC DISK DRIVER
DSKIO
Inputs:
[P] = Carry flag reset for read,
set for write
[Al = Drive number (starts at 0)
[B] = Number of sectors to read/write
tCI = Media descriptor
[DE] = Logical sector number (starts at 0)
EHL] = Transfer address
Outputs:
If successful, carry flag cleared.
Otherwise, carry flag set,
error code is placed in [Al,
number of remaining sectors
in CB] .
Registers:
AF, BC, DE, HL, IX, IY may be affected.
The drive number and media descriptor come from the drive
parameter block. The number of sectors may range from 1
to 255. The logical sector numbers start at zero and is
incremented in ones, so the I/O system must map these the
logical sector numbers into tracks and sectors. The
logical sector 0 corresponds to track 0, sector 1.
The error codes are defined as follows:
0 Write protected
2 Not ready
4 Data (CRC) error
6 Seek error
8 Record not found
10 Write fault
12 Other errors
258
MSX-DOS AND DISK BASIC DISK DRIVER
DSKCHG
Inputs:
[A] = Drive number
CBJ =0
[C] = Media descriptor
[HLl = Base address of DPB
Outputs:
If successful:
Carry flag reset,
tB] = Disk change status
1 Disk unchanged
0 Unknown
-1 Disk changed
ELSE:
Carry flag set,
Error code in [A] (same as DSKIO above)
[NOTE]
If the disk has been changed or may have been
(Unknown), read the boot sector or the first byte
FAT of the currently inserted disk and transfer a
as with the GETDPB call described below.
Registers:
AF, BC, DE, HL,IX, IY may be affected.
changed
of the
new DPB
259
MSX-DOS AND DISK BASIC DISK DRIVER
GETDPB
Inputs:
lA] = Drive number
[B] = First byte of FAT
tC] = Media descriptor
[HL] = Base address of DPB
Outputs:
[HL+1] .. [HL+18] = DPB for the specified drive
The Drive Descriptor Block (DPB) is defined as follows:
MEDIA
Byte
SECSIZ
Word
DIRMSK
Byte
DIRSHFT
Byte
CLUSMSK
Byte
CLUSSHFT
Byte
FIRFAT
Word
FATCNT
Byte
MAXENT
Byte
FIRREC
Word
MAXCLUS
Word
FATSIZ
Byte
FIRDIR
Word
Note
that the
Media type
Sector size (Must be 2 A n )
(SECSIZ/32) -1
Number of one bits in DIRMSK
(Sectors per cluster)-1
(Number of one bits in CLUSMSK)+1
Logical sector number of first FAT
Number of FATs
Number of directory entries (Max=254)
Logical sector number of where the data
area starts
(Number of clusters on drive [not
including reserved sectors, FAT sectors,
or directory sectors])+1
Number of sectors used
FAT logical sector number of start of
directory
logical sector number always begins at zero.
260
MSX-DOS AND DISK BASIC DISK DRIVER
CHOICE
Returns in [HL3 the pointer to the character string
(terminated by a zero) that is used as a user prompt in
menu form by the main code. The simplest form of the
routine be as follows.
CHOISE: LD HL,CHOMSG
RET
♦
t
CHOMSG: DEFB '1 - Single sided, 8 sectors',CR,LF
DEFB '2 - Single sided, 9 sectors',CR, LF
DEFB '3 - Double sided, 8 sectors',CR,LF
DEFB '4 - Double sided, 9 sectors',CR,LF
DEFB 0
If there is no choice (i.e. , only one format is supported),
return with 0 in [HL] register.
All registers except SP may be affected.
261
MSX-DOS AND DISK BASIC DISK DRIVER
DSKFMT
Formats a disk, both physically and logically. The input
parameters are as follows.
[A] Choice specified by the user (1 to 9).
Meaningless unless there is a choice.
CD3 Drive number, beginning at zero
IHL] Beginning address of the work area which
can be used by the format process.
[BC] Length of the work area described above.
All registers except SP may be affected.
This routine formats all of the disk's tracks physically,
writing the boot sector, and clearing FATs and directory
entries.
'Clearing FATs' means:
Writing the media descriptor byte at the first
byte, writing OFFH at the second and the third
byte, and filling the remainder with 0's
'Clearing directory entries' means:
Filling all bytes with 0's
If the format ends successfully, return with carry
flag reset, otherwise return with carry flag set.
The error codes are defined as follows:
0 Write protected
2 Not ready
4 Data (CRC) error
6 Seek error
8 Record not found
10 Write fault
12 Bad parameter
14 Insufficient memory
16 Other errors
[NOTE]
No prompting messages should be generated by this routine.
OEMSTATEMENT
Statement for system expansion for use by OEMs. After
disk BASIC scans its own expanded statements, control is
passed to this entry. The calling sequence is identical
to using a general-purpose expansion statement handler.
If your ROM does not have expansion statements, set the
carry flag and do a Z80 'RET' instruction.
262
MSX-DOS AND DISK BASIC DISK DRIVER
*****************************************
* *
* Some useful external routines *
* *
*****************************************
PROMPT
Prints a message as follows and waits for the user to
enter a key from the keyboard.
1 Insert diskette for drive X:
and strike a key when ready'
The 'X' is the drive name of the current target drive of
your cartridge.
SETINT
This routine saves a previously set interrupt hook to a
location specific to your cartridge, and sets the new
interrupt hook. The address of the interrupt routine
should be passed via the [HL3 register. See DSKDRV.Z80
for details.
PRVINT
This routine jumps to the interrupt hook that you might
have overwritten. Requires no argument. See DSKDRV.Z80
for details.
GETSLOT
Gets the slot address (i.e., where I am) in CAI.
Preserves DE, IX, IY
GETWRK
Gets the base of the work area in [IX] and [HLJ.
Preserves DE, IY
DIV16
[BC1=[BC]/[DE], remainder in [HLl.
Preserves DE, IX, IY
ENASLT
Enables a slot at an address specified by tA] and [HLJ ,
respectively. Destroys all registers.
XFER
Moves [BCJ bytes from [HLJ to [DE] (i.e., LDIR)
Preserves AF, IX, IY
BC is set to 0, HL, and DE pointing to the next location
of source and destination, respectively.
Use this routine when a read/write operation is requested
to 4000H..7FFFH, and your hardware does not have any
special mechanism to transfer directly to these areas.
263
MSX-DOS AND DISK BASIC DISK DRIVER
*****************************************
* *
* External variables *
* *
*****************************************
$SECBUF
Pointer to a temporary storage which is at least SECLEN
byte long. Prepared for use combined with the XFER
subroutine described above, but can be used TEMPORARILY
for any purpose.
RAMADO, RAMAD1, RAMAD2, RAMAD3
Slot address of RAM (if present) at
0000H..3FFFH, 4000H..7FFFH, 800OH..BFFFH, COOOH.FFFFH
respectively.
RAWFLG
Read-After—Write flag. When this byte contains non-0
value, the disk driver should do a read-after-write check.
However, it is completely up to the driver whether to do
the check or not.
264
MSX-DOS AND DISK BASIC DISK DRIVER
How to determine media types
a) Read the boot sector (track 0, sector 1) of the target drive.
b) Check if the first byte is either 0E9H or 0EBH (the JMP
instruction on the 8086)
c) If step b) fails, the disk is a version prior to MS-DOS 2.0;
therefore, use the first byte of FAT passed from the caller and
make sure it is between 0F8H and OFFH.
If step c) is successful, use this as a media descriptor.
If step c) fails, then this disk cannot be read.
d) If step b) succeeds, read bytes # OB to # ID. This is the
DPB for MS-DOS, Version 2.0 and above. The DPB for MSXDOS can
be obtained as follows.
Contents of MS-DOS boot sector
+00
0 E9H, XX, XX or 0EBH, XX, XX
+03
ASCII string of OEM name
+0B
Bytes per sector
(low)
+0C
(high)
+0D
Sectors per cluster
+0 E
Number of reserved sectors
(low)
+0 F
(high)
+10
Number of FATs
+11
Number of directory entries
(low)
+12
(high)
+13
Total number of sectors in the media
(low)
+14
(high)
+15
Media descriptor
+16
Number of sectors per FAT
(low)
+17
(high)
+18
Sectors per track
(low)
+19
(high)
+1A
Number of heads
(low)
+1B
(high)
+1C
Number of hidden sectors
(low)
+1D
(high)
265
MSX-DOS AND DISK BASIC DISK DRIVER
MS-DOS Disk formats
For 3, 3.5, and 5 inch disks (IBM PC format)
First digit :
Second digit:
Third digit :
track number 8=80, 4=40
Sector count 8 or 9
Head count I or 2
1-—- — --
-*1—
- T“
--
- f—
-Tf
-
- 1—
-
-1
1
1
891 1
892 i
881 l
8821 1
491 i
492 1
481 1
482 f
-+-
- 1 -
—-H-
- 4 —
-4-4-
- -| -
^ *--
— -f* - ■
-4
1 Root directory
1
112 1
112 1
1121
1121 1
641
1121
64!
1121
1 entry
1
1
1
1
1 1
1
1
1
1
-+-
-4—
- +_
-“I—'
-4-4--
- h-
— --1-
-+_
- 1
iMedia descriptor 1 0F8HI 0F9HI OFAH 1 OFBHl ll
QFCH10FDH10FEH10FFH1
1 byte (FATID)
1
1
1
1
1 1
1
1
1
1
- +_
- +_
-h—
“ -1- + -
-4—
-4—
-4—
- ^
(Sectors per FAT
1
21
31
11
21 1
21
21
1 1
1 1
-+-
-
-+“
-4—
-4-4--
-4—
-4_.
-4—
- 4
1 Sectors/track
1
91
91
81
81 1
9 t
91
81
81
- +—
- +_
- + _
“-"f-
-4-4-
-4—
-1~_.
-+“
-4
(No. of sides
1
11
21
11
21 1
1 1
21
11
21
- ~h~
- +-
- 4_.
-4~.
-4-4-
-+_
-1-_.
-4—
-4
1 Tracks/side
i
80 1
80 1
80 1
80! 1
40 !
40 1
40 1
40 1
1-
-+-
■-h
-4—
-1—
-4-4-
-
-4—
-+_
-4
iBytes/sector
i
5121
5121
5121
5121 1
512 1
5121
5121
5121
“+"■
-+_
--f-~
-4—
-4-4-
-4—
-4—
-4—
-4
iNo. of FATs
i
21
21
21
21 1
21
21
21
21
-+-
“ “ “—f—
-4—
-4—
-4-4-
-4—
-
-4—
- 1
1 Sectors/cluster
i
21
2!
21
21 1
11
21
1!
21
--i—
-1— ,
-1-
-1_.
-U-L-
_U~
_L_,
_l_
— —— 4
266
MSX-DOS SYSTEM CALLS
3.6 MSX-DOS System Calls
1) File Control Block (FCB) and Directory Entry
User-set record size (Default=128 bytes)--.
I
r- Drive name (0=default, 1=A:) Current block I
I I I
+00 I I
r-H- ---1 -t-
I I File name I I I
L-+- H H-h--|-H-+--H-H-H-H-H-H-H- J
+16
r ~* “ ^ +" “ " +" — “ +“— +” — — "f—-+—— — +“-+" " “ 4— — — *1— — — +— — — +— — — 4— — — +— — i
I File size t Date I Time III I I I
III I I
Device ID —* I I I I
11 I I
Directory location - J I I I
I I I
First cluster of a file - J I I
I I
Last cluster accessed — 1 I
Last cluster (relative to the beginning of a file) accessed J
p- Current record
I
+3 2
p-r-1-i-1-r
I 1 Random record I
1 --|———i-j———4—— — i
size is greater than 63
size is less than 64
I < —Valid—> I
I
I <-Val id—
■*1
If record
If record
Directory format
+00
File attributes
I
--1-1—
I File name I I
h———H— — —I—- — -I-1—
+16
)-^4--(— |-|- y— |— |— 1-1—
I I Time I Date I First I
—-t-H-H-H
-H-H-H--4
File size I
J
First cluster of a file - J
267
MSX-DOS SYSTEM CALLS
2) Drive Parameter Block (DBP)
+00
- Drive number
i— Media ID byte
I r— Sector size
I I r— Directory mask
I l I i— Directory shift
I I II r— Cluster mask
I l III i— Cluster shift
I | I I I I ■— First FAT sector
| | I I I I I *— # of FATs
I | I I I I I I r— # of direct
I I I I I I I II entries
ory
I III I
I III 1 — Pointer to FAT
I I I *— First directory sector
l I 1 — # of sectors per FAT
I 1 — # of clusters + 1
*■— First data sector
3) File Allocation Table (FAT)
MSB LSB
0
r — 1
o
-J 1
1
06
05
04
03
02
01
00
n
1
1
4
PAT
n
1
1 03
i
02
01
00
■1
111
1.
10
09
08
1
l
2
in
10
09
08
07
06
05
04
“H
i
FAT
1
3
1 07
06
05
04
03
02
01
00
1
l
PAT
0
4
103
1
02
01
00
111
10
09
08
i
4
5
in
10
09
08
07
06
05
04
i
_ a
FAT
3
268
MSX-DOS SYSTEM CALLS
4) System call entry
F37DH - MSX disk BASIC
00OSH - MSX-DOS
To invoke a system call, call this entry with C register
containing the function number.
5) System call specification
[Notes]
1) 'Compatibility' means 'compatibility with CP/M'.
CP/M is a registered trademark of Digital
Research, Inc.
2) Function calls entitled 'no function' will only
return a 0 in the A register.
00 SYSTEM RESET
Parameters:
Returns:
Function:
Compatibil ity:
01 CONSOLE INPUT
Parameters:
Returns:
Function:
Compatibil ity :
02 CONSOLE OUTPUT
Parameters: E
Returns: None
Function: Outputs character in E to the console.
Compatibility: Yes
None
A
Inputs a character from the console.
Checks control-C and does function 00.
Checks control-p and begins echoing to
the printer.
Checks control-N and stops echoing to
the printer.
Echoes the input character.
Yes
None
None
If MSX-DOS
Jumps to 0O00H.
El se
Jumps to warm start of disk BASIC.
Yes
269
MSX-DOS SYSTEM CALLS
03 AUX INPUT
Parameters: None
Returns: A
Function: Inputs
Compatibility: Yes
character from an AUX device.
04 AUX OUTPUT
Parameters:
Returns:
Function:
Compatibility:
E
None
Outputs character in E to an AUX device.
Yes
05 LST OUTPUT
Parameters:
Returns:
Function:
Compatibility:
E
None
Outputs character
Yes
in E to the printer.
06 DIRECT CONSOLE I/O
Parameters:
Returns:
Function:
Compatibility:
E
A
If E is OFFH
If no input from the console
Returns 0.
Else
Returns the code.
No check.
No echo.
Else
Outputs character in E to the console.
Yes
07 DIRECT INPUT
Parameters:
Returns:
Function:
Compatibility:
None
A
Inputs character from the console.
No check.
No echo.
No (get I/O byte)
270
MSX-DOS SYSTEM CALLS
0 8 DIRECT INPUT
Parameters:
Returns:
Function:
Compatibil ity:
None
A
Inputs character from the console.
Checks for control-C.
Checks for control-P.
Checks for control-N.
No echo.
No (set I/O byte)
09 STRING OUTPUT
Parameters:
Returns:
Function:
Compatibility:
DE
None
Outputs the string pointed to by
DE to the console until a '$' is en¬
countered in the given string.
Yes
OA BUFFERED INPUT
Parameters:
Returns:
Function:
Compatibility:
DE
None
Inputs the string from console beginning
at IDE+2J until carriage return is
input.
[DE+1] is set to the length of input
string, not including the terminator.
The maximum length of the string is
passed via [DE].
Yes
OB CONSOLE STATUS
Parameters:
Returns:
Function:
Compatibility:
None
A
If no input from the console
Returns 0.
Else
Returns OFFH.
Yes
0C GET VERSION NUMBER
Parameters: None
Returns: H, L
Function: Sets 0
Compatibility: Yes
in H register, 22H in L register.
271
MSX-DOS SYSTEM CALLS
OD DISK RESET
Parameters:
Returns:
Function:
Compatibil ity:
None
None
Sets default drive to (A:).
Sets transfer address to 80H.
Flushes out all sectors which have
been changed but have not been written
to disk.
Yes
OE SELECT DISK
Parameters:
Returns:
Function:
Compatibil ity:
E
None
Sets the default drive, (with a 0
corresponding to A:)
Yes
OF OPEN FILE
Parameters:
Returns:
Function:
Compatibility:
DE
A
Opens a file specified by an FCB pointed
to by DE.
The record size field, the current
block field, the current record field,
and the random record field should
be set after this function is executed.
The file size field, the date and time
fields, the device ID field, the
directory location field, the first
cluster field, the last cluster field,
and the last accessed cluster field
is copied from the directory.
If successful
Returns 0.
Else
Returns OFFH.
Yes
272
MSX-DOS SYSTEM CALLS
10 CLOSE FILE
Parameters:
Returns:
Function:
Compatibility:
DE
A
Closes a file specified by an FCB
pointed to by DE.
If successful
Returns 0.
El se
Returns OFFH.
Yes
11 SEARCH FIRST
Parameters:
Returns:
Function:
Compatibility:
DE
A
Searches for the first occurrence of
a file specified by an FCB pointed to
by DE.
If found
The directory entry (32 bytes long)
is copied to the transfer address.
Returns 0.
El se
Returns OFFH.
[Note]
Wild card characters such as (* and
?) are permitted in the file name.
Yes
12 SEARCH NEXT
Parameters:
Returns:
Function:
Compatibility:
None
A
Searches for the next occurrence of
a file specified by the last 'search
first' function call.
If found
The directory entry (32 bytes long)
is copied to the transfer address.
Returns 0.
Else
Returns OFFH.
[Note]
Wild card characters such as (* and
?) are permitted in the file name.
Yes
273
MSX-DOS SYSTEM CALLS
13 DELETE PILE
Parameters:
Returns:
Function:
Compatibility:
DE
A
Deletes a file specified by an FCB
pointed to by DE.
If successful
Returns 0.
Else
Returns OFFH.
[Note]
Wild card characters such as (* and
?) are permitted in the file name.
Yes
14 SEQUENTIAL READ
Parameters:
Returns:
Function:
DE
A
Reads a record of a file specified
by the FCB pointed to by DE and
transfers the record to the transfer
address.
The record is determined by the current
block field and the current record
f iel d.
The current block field and the current
record field are automatically
incremented upon return.
The record size is always 128 bytes.
If successful
Returns 0.
Else
Returns 1.
[NOTE]
This system call is prepared to maintain
compatibility with CP/M. The use of the 1 random
block read' function is strongly recommended.
Compatibility: Yes
274
MSX-DOS SYSTEM CALLS
15 SEQUENTIAL WRITE
Parameters:
Returns:
Function:
DE
A
Writes a record to a file specified
by the FCB pointed to by DE from the
transfer address. The record is deter¬
mined by the current block field and the
current record field.
The current block field and the current
record field are automatically
incremented upon return.
The record size is always 12 8 bytes.
If successful
Returns 0.
Else
Returns 1.
[NOTE]
This system call is prepared to maintain
compatibility with CP/M. The use of the 'random
block write' function is strongly recommended.
Compatibility: Yes
16 CREATE FILE
Parameters:
Returns:
Function:
Compatibility:
DE
A
Creates a file specified by an FCB
pointed to by DE. If the specified
file already exists, it is overwritten.
The record size field, the current
block field, the current record field,
and the random record field should
be set after this function is executed.
If successful
Returns 0.
Else
Returns OFFH.
Yes
275
MSX-DOS SYSTEM CALLS
17 RENAME PILE
Parameters:
Returns:
Function:
Compatibility:
DE
A
Renames a file name specified by an
FCB pointed to by DE to a file name
specified by an FCB pointed to by DE+16.
If successful
Returns 0.
Else
Returns OFFH.
[Note]
Wild card characters such as (* and
?) are permitted in the file name.
Yes
18 GET LOGIN VECTOR
Parameters:
Returns:
Function:
Compatibil ity:
None
HL
Returns a bit table for on-line drives.
Unlike CP/M, all system drives are on¬
line .
Yes
19 GET DEFAULT DRIVE NAME
Parameters:
Returns:
Function:
Compatibility:
None
A
Gets the default drive name.
Yes
1A SET DMA ADDRESS
Parameters:
Returns:
Function:
Compatibility:
DE
None
Sets transfer address.
Yes
276
MSX-DOS SYSTEM CALLS
IB GET ALLOCATION
Parameters:
Returns:
Function:
Compatibility:
E
A, BC, DE, HL, IY
Returns information of a drive specified
by E.
If drive name is valid
A = Number of sectors/cluster
BC = Sector size
DE = Number of clusters on disk
HL = Number of free clusters
IX = Pointer to DPB
IY = Pointer to FAT
Else
A = OFFH
No (Get allocation address)
277
MSX-DOS SYSTEM CALLS
System calls for CP/M version 2.0 or later
1C NO FUNCTION
Compatibility: No (Set write protect vector)
ID NO FUNCTION
Compatibility: No (Get write protect vector)
IE NO FUNCTION
Compatibility: No (Set file attributes)
IF NO FUNCTION
Compatibility: No (Get disk parameter address)
20 NO FUNCTION
Compatibility: No (Set/Get user code)
21 RANDOM READ
Parameters: DE
Returns: A
Function: Reads a record of a file specified
by the FCB pointed to by DE and
transfers the record to the transfer
address.
The record is determined by the random
block field. The random block field
is not affected by this function.
The record size is always 128 bytes.
If successful
Returns 0.
Else
Returns 1.
[NOTE]
This system call is prepared to maintain
compatibility with CP/M. The use of the 'random
block read' function is strongly recommended.
Compatibility: Yes
278
MSX-DOS SYSTEM CALLS
22 RANDOM WRITE
Parameters:
Returns:
Function:
DE
A
Writes a record to a file specified
by the FCB pointed to by DE from the
transfer address. The record is
determined by the random block field.
The random block field is not affected
by this function.
The record size is always 128 bytes.
If successful
Returns 0.
Else
Returns 1.
[NOTE]
This system call is prepared to maintain
compatibility with CP/M. The use of the 'random
block write' function is strongly recommended.
Compatibility: Yes
23 GET FILE SIZE
Parameters:
Returns:
Function:
Compatibility:
DE
A
Calculates the file size (a multiple
of 12 8) of the file specified by the
FCB pointed to by DE, and sets the
file size to the random record field
of the given FCB.
If successful
Returns 0.
Else
Returns OFFH.
Yes
24 SET RANDOM RECORD
Parameters:
Returns:
Function:
Compatibil ity:
DE
None
Calculates the current record position
from the current block field and the
current record field of the given FCB
pointed to by DE, and sets the record
position to the random record field
of the given FCB.
Yes
279
MSX-DOS SYSTEM CALLS
System calls for CP/M version 2.2 or later
25 NO FUNCTION
Compatibility: No (Resets disk drive)
26 RANDOM BLOCK WRITE
Parameters:
Returns:
Function:
Compatibility:
DE, HL
A
Writes records to a file specified
by the FCB pointed to by DE from the
transfer address. The record is
determined by the random block field.
The current random record field is
automatically incremented upon
successful return. The record size is
determined by the record size field.
The number of records to write is passed
via HL.
If successful
Returns 0.
Else
Returns 1.
No (No function)
27 RANDOM BLOCK READ
Parameters:
Returns:
Function:
Compatibil ity:
DE, HL
A, HL
Reads records of a file specified by
the FCB pointed to by DE and transfers
the record to the transfer address.
The record is determined by the random
block field. The current random record
field is automatically incremented
upon successful return.
The record size is determined by the
record size field.
The number of records to read is passed
via HL.
The number of records actually read is
returned in HL.
If successful
Returns 0 in A.
Else
Returns 1 in A.
No (No function)
280
MSX-DOS SYSTEM CALLS
28 RANDOM WRITE WITH ZERO FILL
Parameters:
Returns:
Function:
DE
A
Writes a record to a file specified
by the FCB pointed to by DE from the
transfer address. The record is
determined by the random block field.
The random block field is not affected
by this function.
The record size is always 128 bytes.
When extending a file, all records that
are not written are filled with 0's.
If successful
Returns 0.
Else
Returns 1.
Compatibility: Yes
281
MSX-DOS SYSTEM CALLS
System calls for MSX-DOS only
29 NO FUNCTION
Compatibility: No
2A GET DATE
Parameters:
Returns:
Function:
Compatibil ity:
26 SET DATE
Parameters:
Returns:
Function:
Compatibil ity:
2C GET TIME
Parameters: None
Returns: H, L, D, E
Function: H = hours
L = minutes
D = seconds
E = 1/100 seconds
Compatibility: No
HL, DE
A
Sets current date to the date passed
via registers.
The registers are as for 'get date'.
If successful
Returns 0.
Else
Returns OFFH.
No
None
HL, DE, A
HL - year
D = month
E = day
A = day of the week
No
282
MSX-DOS SYSTEM CALLS
2D SET TIME
Parameters:
Returns:
Function:
Compatibility:
H, L, D, E
A
Sets current time to the date passed
via registers.
The registers are as for 'get time'.
If successful
Returns 0.
Else
Returns QFFH.
No
2E SET/RESET VERIFY FLAG
Parameters:
Returns:
Function:
Compatibil ity:
E
None
If E is 0
Reset verify flag.
Else
Set verify flag.
No
2F ABSOLUTE DISK READ
Parameters:
Returns:
Function:
Compatibility:
DE, H, L
None
Read H sectors from logical sector
number DE on the drive specified by
L to the transfer address.
No
3 0 ABSOLUTE DISK WRITE
Parameters:
Returns:
Function:
Compatibility:
DE, H, L
None
Write H sectors to logical sector number
DE on the drive specified by L from
the transfer address.
No
283
MSX-DOS SYSTEM CALLS
6) Direct BIOS access of MSX-DOS
On many CP/M application programs, the BIOS jump table is directly
referenced by adding offsets to the contents of addresses 1 and
2. To make the above programs work, MSX-DOS creates a CP/M-style
BIOS front end, vectored by the contents of addresses 1 and 2.
Due to the differences in file handling between MSX-DOS and CP/M,
only the following entries are guaranteed.
BOOT Cold boot
WBOOT Warm boot
CONST Console status
CONIN Console input
CONOUT Console output
284
MSX-DOS SYSTEM CALLS
7) Zero page usage and
00 JP WBOOT
01
02
03
04
05 JP BDOS
06
07
08
09
0A
0B
0C JP RDSLT
OD
OE
OF
10
11
12
13
14 JP WRSLT
15
16
17
18
19
1A
IB
1C JP CALSLT
ID
IE
IF
20
21
22
23
24 JP ENASLT
25
26
27
28
29
2 A
2B
2C
2D
2E
2F
memory map of MSX-DOS
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
285
MSX-DOS SYSTEM CALLS
30
JP
CALLF
(Used)
31
(Used)
32
(Used)
33
34
35
36
37
38
JP
INTRPT
(Used)
39
(Used)
3A
(Used)
3B
—
“1
3C
1
3D
1
3E
1
3F
1
40
1
41
1
42
1
43
1
44
1
45
1
46
1
47
1
48
1
49
1
4 A
1
4B
4C
h -
|
Routine to switch
secondary slot
4D
1
(Used)
4E
1
4F
1
50
1
51
1
52
1
53
1
54
1
55
1
56
1
57
1
58
1
59
1
5A
1
5B
—
J
286
MSX-DOS SYSTEM CALLS
5C FCB for first argument
5D
5E
5F
60
61
62
63
64
65
66
67
68
69
6A
6B
6C FCB for second argument
6D
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7 E
7F
80 Default DMA address
m •
FF
100 TPA
The word at addresses 6 and
memory + 1' for the TPA.
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
(Used)
7 contains the 'highest available
287
MSX-DOS SYSTEM CALLS
The entry addresses for RDSLT, WRSLT, ENASLT, CALSLT, and CALLF
are identical to the ROM BIOS. However, pay GREAT attention when
using these entries directly. You must make sure that the stack
area is guaranteed when changing slots. For example, when calling
the ROM BIOS routines from MSX-DOS through CALSLT, page 0 is set
to ROM, and when an interrupt occurs when the ROM BIOS is active.
Page 1 may be set to ROM (i.e., the disk ROM), because some
manufacturers are using the timer interrupt hook to stop the motor.
[Memory Map]
Page 3
RAM
Page 2
Page 1
Page 0
r ———-—i
ROM
BIOS
r— — —— —
l
i
T
1
1
l
1 RAM
1
1
1
1
1
1
1
1
1
1
1
1 f
1 1
[Disk 1
1 RAM
1
1 ROM 1
i 1
1
1
1
l l
1 #1 1
1 1
1
J
i--a
i-*
Disk I
ROM I . .
I
#2 I
I
RAM I
L
1 - Always contained at 1 non-expanded slot #0*
'secondary slot #0 of expanded slot #0'
or
288
MSX-DOS SYSTEM CALLS
FCB organization (for disk BASIC)
NOTE
The following information is
only for use by advanced pro¬
grammers. Please ignore it if
you do not understand it.
The FCB holds information about file channels. Each channel is
allocated 265 bytes, 9 bytes of which are used by the BASIC
interpreter, and the other 256 bytes for buffering.
lOffsetl Label
1 1 (For SPCDSK)
1 Meaning
1 (For MSX Disk BASIC)
1
1
1 +0
1 FL.MOD
1 Mode which the file was
opened for
-4
l
1 +1
1 FL.FCA
1 Pointer to FCB for BDOS
(low)
1
1 +2
1 FL.LCA
1 Pointer to FCB for BDOS
(high)
1
1 +3
1 FL.LSA
1 Back up character
1
1 +4
I FL.DSK
1 Device number
1
1 +5
1 FL.SLB
1
|
1 +6
1 FL.BPS
1 Position in FL.BUF
1
1 +7
1 FL.FLG
1 Holds various information
1
1 +8
1 FL.OPS
1 Pseudo head position
1
1 +9..
1 FL.BUF
1 256-byte file buffer
1
1 __
- J- —-
- J-
4
289
RS-232C SUPPORT
4. Other Expansions
4.1 MSX RS-232C Support
4.1.1 Extended BASIC for RS-232C Communication
1) Set up Communication Parameters
2) Open and Close Communication Channels
3) Sequential Input and Output
4) Program Load/Save Statements
5) Event Trap Control Statements
6) Miscellaneous Control Statements
7) Functions
8) Terminal Mode
9) Help Function (Optional)
10) Behavior of Control Signals
11) Handling of EOF
4.1.2 Extended BIOS Calls Handling RS-232C
Build a Slot Address Table Entry to the Jump Table
Return Number of Channels
Description of each Extended BIOS Call
4.2 Other MSX Extended BIOS Calls
4.2.1 Extended BIOS Calls
1) Broad Cast Command
2) System Exclusive Extended BIOS Call
3) Summary of Extended BIOS Calls
4.2.2 Extended BIOS Maker ID Number
4.3 Ter.key Support on MSX
290
RS-232C SUPPORT
4.1 MSX RS-232C Support
This section describes the specifications of the support for the
RS-232C communication interface on MSX computers.
4.1.1 Extended BASIC for RS-232C Communication
1) Set up Communication Parameters
CALL COMINI [([<string exp>][,[<Rx baud rate>][,[<Tx baud rate>]
[,[<time out>]3 ] J) ]
Initializes an RS-232C port with the specified parameters. The
<string exp> is a string that specifies the channel control
parameters. See the detailed desciption below.
BAUD RATE
It is possible to set a different baud rate for transmitter and
receiver. The possible baud rates are as follows:
50 110 600 1800 2400 4800 9600
75 300 1200 2000 3600 7200 19200
When only the receiver's baud rate is specified, the baud rate
for the transmitter assumes the same speed as the receiver.
When only the transmitter's baud rate is specified, the baud
rate for the receiver is set to the default value.
If a negative value is specified, its absolute value is written
to i8253 Timer/Counter directly.
TIME OUT
The RS-232C driver waits for the CTS (Clear To Send) to turn on
or/and XON is received when the character is sent. The driver
generates a time out error if the specified time has elapsed.
The value for the time out error is specified in seconds. If
zero (0) is specified, the driver does not generate a time out
error, and the driver waits indefinitely.
291
RS-232C SUPPORT
STRING FIELDS
"[0:][8[N[l[X[H[N[N[N]]]]]]]] n
I I I I I I I I I
Channel Number
When the system has more than one
channel, this parameter specifies
the channel number, and it may be
omitted if the system has only one
channel. The default value is 0.
Data length
"5": 5 bits
"6": 6 bits
"7": 7 bits
"8": 8 bits
Parity flag
"E": Even parity
”0": Odd parity
"I": Ignore (Illegal when data
length is 8 bits)
"N": No parity
Length of stop bits
"1"; 1 bit
"2": 1.5 bits
"3": 2 bits
XON/XOFF control
"X": Enable control
"N": Disable control
CTS-RTS hand-shake
"H": Handshaking
"N": No handshaking
Insert Line Feed to buffer when
Carriage Return is received.
"A": Insert Line Feed to buffer
"N": Do not insert
Send Line Feed after Carriage
Return sent.
"A": Do not send Line Feed
"N": Send Line Feed
Shift-in/Shift-out control. Illegal
when data length is other than 7 bits.
"S": Enable control
"N": Disable control
Examples:
CALL COMINI (" 0 : 7E1XHNNN" ,600,1200,30)
CALL COMINI (" 8N1" , 96 00)
The default values for those switches are as follows:
"0:8E3XHNNN",1200,1200,0
Note that no previous value is taken as the default. If
omitted, the above values are always assumed.
292
RS-232C SUPPORT
2) Open and Close Communication Channels
OPEN "COM[n]: n [FOR <mode>] AS [#] <file number>
This statement opens the RS-232C channel for further
processing. That is, a I/O buffer is allocated and the mode
that will be used with the buffer is set. The RTS signal is
also activated.
The <mode> is one of the following:
OUTPUT: Specifies sequential output mode
INPUT : Specifies sequential input mode
If the <mode> clause is not specified, the channel can be
accessed for both input and output and no EOF character
handling is done.
The <file number> is an integer expression whose value is
between one and the maximum number of files specified in a
MAXFILES= statement.
The <file number> is the number that is associated with the
file for as long as it is OPEN and is used by other I/O
statements reffering to the file.
An OPEN statement must be executed before I/O may be done to
the file using any of the following statements. The OPEN
statement must be executed before any statement or function
requiring a file number:
PRINT #, PRINT # USING
INPUT #, LINE INPUT #
INPUTS
Example:
OPEN "COMO:" AS #1
NOTE
Random access to RS-232C channel is
not possible. Logically, only sequential
accesses are permitted.
CLOSE [[#]<file number >[ ,<file number>]3
Closes the channel and releases the associated buffer. If no
<file number>s are specified, all open channels are closed.
If the channel was opened in output mode, the EOF character is
sent.
293
RS-232C SUPPORT
3) Sequential Input and Output
After the channel is opened in input mode or file mode (open
without <mode> clause), characters from communication channel
can be sequentially input by one of the following statements.
INPUT #n
LINE INPUT #n
INPUT$ (#n,m)
After the channel is opened in output mode or file mode (open
without <mode> clause),characters can be sequentially output to
the communication channel by one of the following statements.
PRINT #n
PRINT #n USING
Refer to the reference manuals for the language for details on
the statements.
4) Program Load/Save Statements
SAVE n COM[<n>: 3 " [, A]
Sends a BASIC program to the communication channel. A Control-Z
is treated as the end-of-file character. The program is sent
in ASCII format, whether the optional parameter, "A", is
specified or not. No file name is allowed.
LOAD "COM[<n>:]“
Loads a BASIC program from the channel. A LOAD statement closes
all open files and deletes the current program from memory. If
the "R" option is specified, however, all data files remain
OPEN and the program that is loaded is also executed. A
Control-Z is treated as the end—of—file character.
MERGE "COM[<n>: ] "
Merges lines from a program in ASCII format received through
the communication channel into the program currently in memory.
If some of the line numbers of the program in memory match line
numbers of the incoming (channel) program, the lines from the
program from the channel replaces the matching lines. A
Control-Z is treated as the end-of-file character.
After the MERGE command, the merged program will reside in
memory, and control will return to BASIC at the command level.
RUN "COM[<n>: ] " [,R]
Loads a program from the channel into memory and runs it.
RUN closes all open files and deletes the current contents of
memory before loading the designated program. When the "R"
option is specified, however, all data files remain OPEN.
294
RS-232C SUPPORT
5) Event Trap Control Statements
CALL COMON("[<n>:]")
Enables event trapping caused by incoming character from the
communication channel.
CALL COMOFF("[<n>:3")
Disables event trapping caused by incoming character from the
communication channel. The communication buffer is flushed.
CALL COMSTOPC [<n>: ] ")
Suspends event trapping caused by incoming character from the
communication channel.
CALL COM ([<n>: ] ,GOSUB Cline number>)
Sets the line numbers for BASIC to trap when characters are
received at the communication channel.
When trap occurs, since CALL COMSTOP is automatically executed,
received traps can never take place. The RETURN from the trap
routine will automatically do CALL COMON unless CALL COMOFF
has been explicitly performed inside the trap routine.
Event trapping does not take place when BASIC is not executing
a program. When an error trap (resulting from an ON ERROR
statement) takes place, it automatically disables all trapping
(including ERROR, STRIG, STOP, SPRITE, INTERVAL and KEY).
6) Miscellaneous Control Statements
An OPEN statement must be executed before any one of following
statements may be executed. The default channel number is 0
for all the following statements.
CALL COMBREAK(["<n>:"],<expression>)
Sends break characters specified by <expression> to the channel
specified by <n>. The range of the <expression> should be
between 3 and 32767.
CALL COMDTR(["<n>:"],<expression>)
Turns off the DTR signal when the <expression> is zero,
otherwise turns on the DTR signal.
CALL COMSTAT (["<n>:"],<name of variable^
Reads the status of the communication channel. The status
returned by the hardware is assigned to the variable. The
bit assignments are as follows:
295
RS-232C SUPPORT
BIT NO.
“ *T - *'
1
*-+-
Description
1
15
i
Buffer Overflow Error
— -l
1
1
0: No buffer overflow
1
1
1: Buffer overflow
1
14
1
Time Out Error ( TMENBT )
1
1
0: No time out error occurred
1
1
1: Time out error occurred
1
13
1
Framing Error
1
1
0: No framing error occurred
1
12
1
1: Framing error occurred
1
1
Over Run Error
1
1
0: No over run error occurred
t
1
1: Over run error occurred
1
11
1
Parity error
I
1
0: Character has no parity error
1
1
1: Character has parity error
1
10
1
Control break key was pressed ( BRONBT )
1
1
0: Control break key not pressed
1
1
1: Control break key was pressed
1
9
1
Not used: Reserved
1
8
1
Not used: Reserved
1
7
1
Clear To Send
1
1
0: False
1
1
1: True
1
6
1
Timer/Counter Output-2
1
1
0: Timer/Counter Output-2 negated
1
1
1: Timer/Counter Output-2 asserted
1
5
1
Not used: Reserved
1
4
1
Not used: Reserved
1
3
1
Data Set Ready
1
1
0: False
1
1
1: True
1
2
1
Break Detect
1
1
0: Not detected
1
1
1: Detected
1
1
1
Ring Indicator
1
1
0: False
I
1
1: True
1
0
1
Carrier Detect
1
1
0: False
1
1
1: True
1
-J-
-1
296
RS-232C SUPPORT
7) Functions
EOF(<file number>)
Returns -1 (true) if the EOF character is received. Otherwise,
returns 0. Use EOF to test for end-of-transmission during
INPUT to avoid 1 Input past end' errors.
LOCKfile number>)
Returns the number of characters received in the communication
buffer. The size of the communication buffer is 255 characters.
LOF(<file number>)
Returns the size of the free space remaining in the
communication buffer.
8) Terminal Mode
CALL COMTERMl("<n>:")
Enters a terminal emulator mode. The channel should be closed
when this statement is invoked. The function keys have a
special use in the terminal mode as described below.
F-6: Toggles the literal mode on/off. In the literal mode,
control characters are displayed, offset by 40H. As an
example,a character whose code is 01H is displayed as "A".
Initial mode: Literal mode off
F-7: Toggles the Half/Full duplex modes. In Half duplex mode,
the characters typed in are echoed to the screen as
well as sent to the communication channel.
Initial mode: Full duplex
F-8: Turn on/off printer echo. When the printer echo is on,
all characters sent to the screen are also echoed to the
printer.
Initial mode: Printer echo off
297
RS-232C SUPPORT
9) Help Function (Optional)
CALL COMHELPl (<n>:) ]
Prints out a brief description of parameters set by
statement on the screen as follows.
Initialize statement options
CALL COMINI ("
<Device# {0,1,2...9}>:
CCharacter length {5,6,7,8>>
<Parity {E,0, I,N}>
<Stop bits {1,2,3>>
<XON/XOFF (X,N>>
<CTS handshaking {H,N>>
<Auto LF on receive {A,N)>
<Auto LF on transmit {A,N}>
<SI/SO (S,N}>"
,<Receiver baud rate>
,<Transmitter baud rate>
)
Default:
CALL COMINI("0:8N1XHNNN"
, 1200 , 1200 , 0 )
a COMINI
298
RS-232C SUPPORT
10) Behavior of Control Signals
RESET COMINI OPEN CLOSE
RTS: Inactive No effect Active Inactive
DTR: Active Active No effect No effect
The RTS signal is affected in the following cases:
1. OPEN statement executed: activated
2. CLOSE statement executed: inactivated
3. The remaining contents of the communication is less than 16
bytes and the CTS-RTS handshake is enabled: inactivated.
4. When inactive and the remaining contents of the communication
buffer has more than one byte and CTS-RTS handshaking is
enabled: activated.
DTR is affected by the CALL COMDTR and CALL COMINI statements.
11) Handling of EOF
An EOF is transmitted when a CLOSE statement is executed during
the open mode was output.
299
RS-232C SUPPORT
4.1.2 Extended BIOS Calls Handling RS-232C
The RS-232C driver can be used by application programs using
the "EXTENDED BIOS CALL" routine. Such programs can access the
functions in the RS-232C driver through the entry jump table
with inter-slot call function provided in the BIOS. Programmers
can determine the location of this table by usinc an EXTENDED
BIOS CALL 0 and 1.
The RS-232C driver is addressed by device number 8. The
functions for the RS-232C driver supported by extended BIOS
calls are described below.
Build a Slot Address Table Entry to the Jump Table
Number: 0
Function: Builds entry address to the jump table in the device
driver pointed by [HL].
Entry: [B] = Slot address of table entry for the device
driver
[HL] = Points to table entry for this device driver
Exit: lB] = Slot address of next table entry
[HLJ = Points to next table entry
Description: The RS-232C device driver call routine can issue
this function call to determine the slot number and
the location of the jump table to access the device
driver for the desired channel.
[B] : [HL]
[B] : [HL] —*
returned*
1 %Slot address
lJump table
address
(L)
(Jump table
address
(H)
1 Reserved
1
—
\
% The format of the slot address is same to the USX standard
notation, which is:
Bit # 76543210
F000SSPP
I Nil
I I I LJ — Primary slot (0-3)
I lx -Secondary slot (0-3)
1 -1 if secondary slot specified
300
RS-232C SUPPORT
Return Number Of Channels
Number: 1
Function: Returns the number of channels available to the
device driver.
Entry: [A] = Contains number of RS-232 channels so far.
Exit: [A] = Number of RS-232 channels updated.
Description: This function is provided for each RS232C driver
so as to find the channel number for the driver.
Each driver can call this function to get the number
of RS-232C channels installed so far.
The device information byte indicates whether the following
options are installed or not:
Bits 76543210
I I I I I I I I
I I I I I I i L -Reserved
I I I I I I I
I I I I I I 1 -TxReady interrupt
I I I I I I
I I 1 I I 1 -Sync/Break character detected
till 1 -Timer interrupt
I | | i-Carrier detect
I I I
! I 1 -Ring indicator
| i-Reserved
I
1 -Reserved
The RS 232C driver has entries as follows. Application programs
can use the RS-232C driver by an ’inter-slot call' to those
entries.
EXBTBL: DEFB
JP
JP
JP
JP
JP
JP
JP
JP
JP
JP
JP
JP
NOENT
NOENT
NOENT
DVINFB,0,0
INIT
OPEN
STAT
GETCHR
SNDCHR
CLOSE
EOF
LOC
LOF
BACKUP
SNDBRK
DTR
Device information
Initialize RS-232C port
Open RS-232C port
Read status
Receive data
Send data
Close RS-232C port
EOF code received
Reports the number of characters in
the receiver buffer
Reports the number of free spaces
left in the receiver buffer
Back up a character
Send break character
Turn on/off DTR line
Reserved for future expansion
301
RS-232C SUPPORT
NOTE
The RS-232C receiver is driven by the
interrupt generated by the receiver ready.
However, the inter-slot call handler dis¬
ables the interrupt automatically. Thus,
when control returns to the application
program, it must enable an interrupt as
soon as possible, or the RS-232C receiver
routine will lose some of the characters.
302
RS-232C SUPPORT
Description of each Extended BIOS Call
1) Initialize RS-232C Port (INIT)
Entry: IHLJ = Address of the parameter table
[BJ = Slot address of the parameter table
Return: The carry flag is set if illegal parameters are set.
Modify: [AF3
Description:
Initializes the RS-232C port with the specified parameters.
This entry must be called before any other function calls are
made. The parameters are similar to the _ COMINI expanded
statement of BASIC. However, note that all the ASCII
parameters must be specified with uppercase characters only.
(See section 4.1.1 CALL COMINI for details of BAUD RATE and
TIME OUT.)
tB3 : EHL]—» I Character Length
--
I Parity 1 E’ , 1 O' , ' I' , 1 N'
f -*-— --— --— — —
I Stop Bits *1 1 ,'2 *3 1
i XON/XOFF Control ,'N'
--
I CTR-RTS Handshaking ' H','N'
I--
I Auto LF for Receiver * A','N'
I Auto LF for Sender ’A’,'N'
I SI/SO Control 'S','N'
i-
I Receiver Baud Rate (Low)
i
I 50-19200 (High)
--
I Transmitter Baud Rate (low)
i
I 50-19200 (high)
w —— - -- *-
I Time Out Counter 0-255
303
RS-232C SUPPORT
2) Open RS-232C port (OPEN)
Entry: [HL]= Address of FCB (must be located higher address
than 8000H)
[C] = Buffer length ( 32~254 )
[E] = Open mode (one of following):
I Open Mode I Meaning I
i-1-—-1
I 1 I <lnput> mode 1
I 2 I <Output> mode I
I 4 I <Raw> and <Input/Output> model
Returns: The carry flag is set if an error occurs.
Modifies: (AF]
Description:
Opens the RS-232C port with the specified File Control Block
(FCB). An Open must be executed before any I/O operations can
be done. Each character received occupies two bytes in the
buffer. One is the received character code itself and the
other is the error status of the received character. An extra
9 bytes are necessary for the working storage for file control.
Note that the buffer length passed by [C] specifies the number
of characters, so the actual length of buffer is [Ci x 2 + 9
bytes. This buffer area can also be accessed without slot
handling whenever the RS232C driver is called (including the
timing when the interrupt from the receiver is generated).
[HLJ—»
I 9 bytes for File Control
tCJ X 2 Bytes Receiver Buffer
n
i
i
i
a
304
RS-232C SUPPORT
3) Read Status (STAT)
Entry: None
Returns:
IHL]= Status Data
Modifies:
None
Description:
Returns
the status information and error code of the
character
3 ust
read
from the buffer (not the character just received).
1 BIT NO
. 1 Description
- 1
1
|-
_
1
15
1 Buffer over flow error
i
1
1 0: No buffer over flow
i
1
1 1: Buffer over flow
i
1
14
1 Time out error ( TMENBT )
i
1
1 0: No time out error occurred
i
1
1: Time out error occurred
i
1
13
1 Framing error
i
1
1 0: No framing error occurred
i
1
1 1: Framing error occurred
i
1
12
1 Over run error
i
1
1 0: No over run error occurred
i
1
1 1: Over run error occurred
i
1
11
1 Parity error
i
1
1 0: Character has no parity error
i
[
S 1: Character has parity error
i
1
10
i Control break key was pressed ( BRONBT )
i
1
1 0: Control-break was not pressed
i
1
' 1: Control-break was pressed
i
1
9
1 Reserved
i
1
8
1 Reserved
i
1
7
1 Clear To Send
i
1
1 0: False
t
1
1 1: True
i
1
6
1 Timer/Counter Output-2
i
1
1 0: Timer/Counter Output-2 negated
i
1
1 1: Timer/Counter Output-2 asserted
i
1
5
1 Reserved
i
1
4
1 Reserved
i
1
3
1 Data Set Ready
i
1
1 0: False
i
1
1 1: True
i
1
2
1 Break Detect
i
1
1 0: Not detected
i
I
1 1: Detected
i
1
1
1 Ring Indicator
i
1
1 0: False
i
i
1 1: True
i
1
0
1 Carrier Detect
i
1
1 0: False
i
t
1 1: True
i
— j
305
RS-232C SUPPORT
4) Get A Character Frcsn The Receive Buffer (GETCHR)
Entry: None
Returns: [A] = character received
The sign flag is set if any error occurred.
The carry flag is set if the character is an EOF code
when the port is opened for input mode.
Modifies: [F]
Description:
Gets a character from the receiver buffer. Returns backed
up character if any.
5) Send A Character To The RS-232C Port (SNDCHR)
Entry: [A] = Character to send
Returns: The carry flag is set if a control-break was entered.
The zero flag is set if a time out error has
occurred while waiting for XON or/and CTS signal.
Modifies: CF 3
Description:
Sends the specified character to the RS-232C port. The
character flow control by XON/OFF characters and/or the CTS
(Clear To Send) line signal is handled if they had been
initialized. A time out error will be generated if the
specified time has elapsed while waiting for transmission
permission, and the character will not be sent.
6) Close The RS-232C Port (CLOSE)
Entry: None
Returns: The carry flag is set if an error occurs,
Modifies: [AF]
Description:
Closes the RS232C port. The buffer is released, and a EOF
code is sent if the port was opened for <output> mode. The RTS
signal is placed in an inactive state.
306
RS-232C SUPPORT
7) Check For The EOF Code (EOF)
Entry: None
Returns: [HL]= -1 , carry flag set, if next character is EOF.
= 0, carry flag reset, if next character not EOF.
Modifies: [AF]
Description:
Tests whether the next character is an EOF or not. Returns 0
if the next character is not EOF.
8) Returns The Number Of Characters In The Receive Buffer (LOC)
Entry: None
Returns: [HL] = Number of character in the receiver buffer.
Modifies: [AF]
Description:
Returns the number of valid characters in the receive buffer.
This value includes number of backed-up characters. The
characters after the EOF code are ignored if the transmission
was opened in the <input> mode; however, they will occupy space
in the buffer.
9) Returns Number Of Free Space In The Receive Buffer (LOF)
Entry: None
Returns: [HL]= number of free space
Modifies: [AF]
Description:
Returns the number of free spaces for characters in the
receiver buffer.
10) Back Up A Character (BACKUP)
Entry: [C3 = Character to back up
Returns: None
Modifies: E F]
Description:
Backs up a character in the special buffer. Last backed up
character will be lost if any.
307
RS-232C SUPPORT
11) Send Break Character (SNDBRK)
Entry: [DE] = Number of break characters to send
Returns: The carry flag is set if control break key was pressed.
Modifies: [AF], [DE]
Description:
Transmits the specified number of break characters. Aborts
if a Control-Break is entered during the transmission and
returns with the carry flag set.
12) Turn On/Off DTR Line (DTR)
Entry: [A] = 0 to turn off
[Al = Non-zero to turn on
Returns: None
Modifies: [F]
Description:
The DTR (Data terminal Ready) line is turned on when a power-on
/reset initialize or an INIT routine is called.
****************************************************
* NOTE *
* *
* Stack pointer must be located in PAGE-3 (higher *
* address than OCOOOH). No registers except those *
* described here should be changed. *
****************************************************
308
OTHER MSX EXTENDED BIOS CALLS
4.2 Other MSX Extended BIOS Calls
The extended BIOS call provides a way to access the extended
device drivers via an additional HOOK entry. The device type is
specified by register D, and the function of the call is specified
by register E. To build a link of an extended BIOS call, each
device driver should nest the Hook properly.
The address of the Hook for the extended BIOS call is: OFFCAH.
The flag bit which indicates whether the HOOK is valid or not
is: LSB of 0FB20H.
NOTE
The stack pointer must be located in PAGE-3 (addresses
higher than OCOOOH). No other registers except those
described here should be changed.
4.2.1 Extended BIOS Calls
1) Broad Cast Command
If the device number specified by register [D] is 0, this call
should handle all extended device drivers added to the system.
Build Device Name Table
Number:
Function:
Entry:
Exit:
Description:
0
Build table which contains device number.
IB] = Slot address of table entry for the device
driver.
[HL] = Points to table entry for the device driver
[B] = Slot address of next table entry
[HL] = Points to next table entry
Using this call, the user is provided information on
the type of device driver that must be installed in
the system. To obtain detailed information, such as
the slot number and the address to access driver,
issue a call with the device number in [D] and the
function number (which is zero) in [E].
' -—- 1
[B];[HL]—41 Device number I
i-—i
I Reserved I
IB] : [HL]
returned*
I
J
309
OTHER MSX EXTENDED BIOS CALLS
Return Number Of Trap Entries Used
Number:
Function:
Entry:
Exit:
Description:
I
Adds number of traps used in device driver to [A].
[A] = Contains number of traps used by extended
device driver so far.
[A] = Number of traps updated
There is a limited number (six) of flags for the
event trap function. This call is provided to
determine the flag to use with this device.
Disable Interrupt
Number:
Function:
Entry:
Exit:
Description:
2
Disables device driver interrupts.
None
None
This function call is provided to inhibit
interrupts. This feature is useful for improving
the interrupt service response time or to inform
the interrupt-drive routine that the DI instruction
is going to issue.
Enable Interrupt
Number:
Function:
Entry:
Exit:
Description:
3
Enables device driver interrupts.
None
None
This function call is provided to allow device
drivers to generate interrupts.
310
OTHER MSX EXTENDED BIOS CALLS
2) System Exclusive Extended BIOS Call
This call is provided to allow the installation of special system
software for proprietary use. The sole function specified follows.
All other functions are not specified.
Device number:255
Number:
Function:
Entry:
Exit:
Description:
0
Builds a table containing the pointer to the BIOS
functions and device information.
CBl = Slot address of table entry for the device
driver.
[HL] = Points to table entry for this device driver.
[B3 = Slot address of next table entry
[HL3 = Points to next table entry
The caller of the device driver can issue this
function call to determine the slot number and the
location of the jump table access the device driver.
[Bl : [HLl
r- —- 1
[B]:[HL]^^l Slot address I
l-—-1
IJump table address (L) t
t---t
IJump table address (H) I
h--4
I Maker ID I
4--^
I Reserved I
I-H
returned—»I I
NOTE
The Maker ID is assigned in response to
requests. Manufacturers who provide unique
Maker IDs must also provide the BIOS spe¬
cifications to the public.
311
OTHER MSX EXTENDED BIOS CALLS
3) Summary of Extended BIOS Calls
I ID] I
Description
1
[E]
l Broad cast
1
f-
0
I Build device name table
I 0
1
1
1 Return number of Trap Entries used
i
\ _
2
1 Disable interrupt
i
- _
3
1 Enable interrupt
i
[E
1 RS-232C
1 8
i
1-
0
1 Build a slot address table
i
- +— -
1
1 Return number of channels
1
1 — -
[E]
1 System exclusive
1 255
i
0
1 Build a slot address table
312
OTHER MSX EXTENDED BIOS CALLS
4.2.2 Extended BIOS Maker ID Number
The Maker ID is assigned in response to requests,
manufacturer not providing a Maker ID listed below
provide the BIOS specification to the public.
r— —- —-—
1 ID code
J----
1
Name of manufacturer
i 0
1
ASCII
i 1
1
MICROSOFT
I 2
1
CANON
1 3
1
CASIO KEISANKI
1 4
1
FUJITSU
1 5
1
GENERAL
1 6
1
HITACHI SEISAKUSYO
1 7
1
KYOCERA
1 8
1
MATSUSHITA DENKI
I 9
1
MITSUBISHI DENKI
1 10
1
NIHON DENKI
1 11
I
NIHON GAKKISEIZOU
1 12
1
NIHON VICTOR
1 13
1
PHILLIPS
1 14
1
PIONEER
1 15
I
SANYO
1 16
1
SHARP
1 17
1
SONY
1 18
1
SPECTRAVIDEO
1 19
1
TOSHIBA
1 20 *
1
1
MITSUMI DENKI
* Added on August 21, 1984
A computer
must also
313
TENKEY SUPPORT
4.3 Tenkey Support on MSX
The
standard
MSX
uses nine
rows of a
key matrix, but
two more rows
(Y9
and Y10)
can
be added
to support
an additional
sixteen
keys.
The
following
is
a list of
the assignments of the additional
keys.
X7
X6
X5
X4
X3 X2
XI
XO
Y 9
4
3
2
1
0 Option
Option
Option
Y10
•
$
-
9
8 7
6
5
(Period) (Comma) (Minus)
(The Option keys may be used for any purpose.)
314
PART D
SOFTWARE DEVELOPMENT GUIDE
INTERNATIONAL MSX VERSIONS
5. International MSX Versions and their Differences
5.1 Introduction
At present, the MSX computer has the following versions. At a
later time, it is possible that other versions will be released
for other countries.
Japanese
USA
International (abbreviated INT in this document)
UK
DIN
French
Korea
5.2 Keyboard
5.2.1 Keyboard Hardware
The KANA key of the Japanese version toggles Kana mode and alpha
mode, but the CODE key of international versions, while occupy
ing the same position on the keyboard matrix, the keyboard input
mode for the entry of the next key. Thus, the LED to indicate
the CODE shift status is unnecessary.
Three keys are pressed simultaneously in the Shift-Graph and
Shift-Code modes. Using ordinary keyboard sense techniques,
the SHIFT, GRAPH, and CODE shift keys must have a diode to
prevent the loopback current that causes scanning conflicts.
316
INTERNATIONAL USX VERSIONS
5.2.2 Character Set
The USA, INT, UK, DIN, and French versions have a common
international character set.
o Character Code Table (International)
01 23456789ABCDEF
NOTE: The font of the character 'O' (zero) is different in DIN
version. See figure.
***
* *
* *
* * *
* *
* *
***
317
INTERNATIONAL MSX VERSIONS
o Character Code Table (Japanese)
01 23456789ABCDEF
318
INTERNATIONAL MSX VERSIONS
5.2.3 Keyboard Layout
See the figures in the next section. The USA and INT versions
have the same keyboard.
About USA, UK, INT versions:
The keyboard diagrams show a dead-key to the left of the
carriage return key, but this is probably not a good place
for it, because it pushes the carriage return key too far to
the right. Manufacturers may place this key another place,
for example, the right of the right-hand shift key.
About DIN, French versions :
Manufacturers may move the less than and greater than keys
(<, >) to the left of the left-hand shift key, but must also
revise the keyboard hardware.
5.2.4 CAPS Lock
In the CAPS-lock mode, the uppercase of characters (having both
a lowercase and an uppercase) is entered. In the CAPS-lock mode
of the Japanese and French versions, when the shift key and an
alphabet key are pressed, the lowercase letter is entered. When
this is done in other (USA, UK, DIN, and INT) versions, an
uppercase letter is entered.
For the French version, see figure. The marked keys in the
figure are shifted by the CAPS-lock. The CAPS-lock is not valid
for the graphics and code characters.
KANA characters in the Japanese version are valid when the KANA-
Lock key is valid. Normally HIRAiGANA charcters are entered, and
with the CAPS-Lock key together, KATAKANA characters are entered.
Most of them are not affected by the SHIFT key. However, some
of the KANA characters have both upper- and lowercase letters
and are shifted by the SHIFT key. Notice the differences in the
decoding charts.
319
INTERNATIONAL MSX VERSIONS
o Layout International (USA)
320
INTERNATIONAL MSX VERSIONS
o Decode International (USA)
n
N
T
0
1
CM
3
4
5
6
7
Normal
0
30
1 1
31
2
32
3
33
4
34
5
35
6
36
7
37
Shift
)
29
j 1 21
«?• 40
It
23
$
24
~%
25
~ 5E
&
26
c
)
Graph
O
09
V*
AC
Vi
AB
% BA
J? EF
%o
RD
r
F4
r
FR
f
Shift
Q OA
■ 2
FD
a
FC
j
F5
Code
S KB
L ]_
9F
$
D9
§
BF
e
9B
y
98
a
EO
0 El
Shift
a
D8
i AD
Pt
9E
r
BE
£
9C
Y
9D
Normal
8
38
9
39
-
2D
=
3D
\
5C
L
5B
i
5D
; 3B
Shift
*
2A
1 ( 28
_
5F
t 2R
; 7c
1 7B
M 7D
: 3 A
1
Graph
RC
•
07
—
17
FI
\
IE
©
01
p
0D
♦
06
1
Shift
D
08
-+- IF
=
F0
1 16
e
02
f)
0E
♦
04
Code
7
E7
c
87
*
EE
8
E9
4>
ED
(i)
DA
U
B7
Shift
1' E2
C 80
0
E8
Q
EA
0
B6
Normal
’ 27
' 60
_
L ^2C
•
2E
/
2F
a
61
b
62
Shift
" 22
■
7E
<
3C
>
3E
7
3F
A
41
B
42
2
)
Graph
4
05
RB
F3
£
F2
/
ID
'
4J
-
C4
_L
11
9
Shift
¥
03
=s
F7
<
AE
)
AF
4-
F6
'O
■ FE
Code
ij
B9
<7
E5
a
86
a
A6
0
A 7
-
— TJ
nr
84
u
97
Shift
IJ
B8
X
E4
A
8F
t
A8
■■
A
8E
--—
Normal
c 63
d
64
e
65
f
66
g
67
h
68
i
69
j
6A
Shift
C
43
D
44
E
45
F
46
G
47
H
48
i
49
J
4A
3
i
Graph
0
RC
d" C7
▼
CD
h
14
+ 15
H
13
m
DC
1 C6
Shift
FA
%
Cl
_
▲
CE
■
D4
1 10
■
06
■
DF
|CA
Code
i 8D
1 8B
1
8C
6
94
ii
81
a
B1
i A1
ae
91
Shift
6
99
u
9A
A
B0
/E
92
Normal
k
6R
1 6C
m
6D
n
6E
()
6F
P
70
q
71
r
72
Shift
K
4B
L
4C
M
4D
N
4E
0
4F
P
50
Q
51
R 52
A
Graph
1 DU
■
C8
0B
J
IB
■l
C2
m
DB
^CC
r
18
Shift
l DE
| C9
?
DC
■
D3
C3
a
D7
/,/
CB
r
A9
Code
i B3
0
B5
ft
E6
it
A4
6
A2
u
A3
a
83
0
93
Shift
]
B2
6
B4
N
A5
1]
E3
Normal
s
73
t
74
11
75!
V
76
w
77
X
78
y
79
Z
7A
Shift
S 53
T
54
U 55
V
56
w
57
X
58
Y
59
z
5A
CJ
Graph
H D2
~r
12
CO
L- 1A
► CF
X
1C
n
19
OF
J
Shift
XD1
■
C5
■
D5
i DO
•
F9
\A
o
F8
e
89
u
96 T
6
82
0
95
e
88
e
8A
a
A0
A
85
■1
m
131
- -1
_J
321
322
INTERNATIONAL MSX VERSIONS
o Decode UK
1
U K
(
D
1
2
3
4
5
6
7
Normal
0
30
1
31
2
32
3
33
4
34
5
35
6
36
7
37
Shift
1
29
! 21
(a-
40
P
23
$
24
%
25
/v.
5E
&
26
0
Graph
rcr
09
1/
/i
AC
14
AB
K
BA
X}
FF
0/
/OO
BD
f
F4
r-
FB
Shift
0 OA
2 FD
a
FC
J
F5
Code
n
EB
f
9F
t
D9
§
BF
i
9B
y
98
a EO
3 El
Shift
£
D8
i AD
Ft
9E
qr
BE
£ 9C
Y
9D
Normal
8
38
9
39
-
2D
-
3D
\
5C
j
5B
"
5D
; 3B
Shift
*
2A
( 28
_
5F
+
2B
; 7C
j 7B
! 7D
: 3A
1
Graph
EC
•
07
— 17
i
FI
r\
IE
© 01
P
OD
♦
06
1
Shift
n
08
-+-
IF
-
FO
16
«
02
/ *
OE
♦
04
Code
7 F7
d 87
£
EF
6
E9
-
60
<t>
ED
OJ
DA
it B7
Shift
T E2
c
80
<t>
E8
2 EA
U
B6
Normal
' 27
£
9C
, 2C
. 2E
X
2F
a
61
b
62
Shift
22
7E
<
3C
>
3E
V
3F
A
41
B
42
CM
Graph
05
BB
F3
F2
/
ID
-
C4
_1_ 11
Shift
03
-
F7
( AE
$
AF
A
F6
X
1
FE
Code
ij
B9
■•7
E 5
a
86
a
A6
0
A7
~ *
a 84
0
97
Shift
u
B8
V
E4
A 8f
i
A8
* '
A
8E
Normal
c
63
cl
64
e
f
66
g
67
h
68
i 69
j
6A
Shift
C
43
D
44
E 45
F
46
G
47
H 48
1 49
J
4A
3
Graph
0
BC
J* C7
▼
CD
h
14
+
15
-|
13
m
DC
S C6
Shift
-
FA
V Cl
▲
CE
■
D4
4
If)
■
D6
■
DF
■
CA
Code
i 8D
V 8B
1
8C
ii 94
ii
81
a B1
f A1
at- 91
Shift
0
99
u
9A
A
BO
JE
92
Normal
1<
6B
1
6C
m
6D
n
6E
<)
6F
P
70
q
71
r
72
Shift
K
4B
L
4C
M
41)
N
4E
0
4F
P
50
Q 51
R
52
4
Graph
H DD
■
C8
0B
J
IB
m
C2
T
DB
CC
r
18
Shift
| DF.
| C9
o.
0C
■
D3
—
C3
&
D7
^CB
r
A9
Code
i B3
6
B5
ft
E6
fi
A4
6
A2
u
A3
a
83
6
93
Shift
1
B2
6
B4
N
A5
ii
E3
Normal
s 73
t
74
11
75
V
76
w
77
X
78
y
79
z
7A
Shift
S
53
T
54
U
55
V
56
w
57
X
58
Y
59
z
5A
5
Graph
H D2
~r
12
_
CO
L
1A
^ CF
X
1C
1
19
*
OF
Shift
XD1
■
C5
■
D5
i DO
•
F9
n
AA
o
F8
Code
e
89
V
96
82
d
95
e
88
6
8A
ft
AO
a
85
Shift
£
90
323
INTERNATIONAL MSX VERSIONS
o Layout DIN
324
INTERNATIONAL MSX VERSIONS
o Decode DIN
D 1
N
0
1
2
3
4
5
6
7
Normal
0
30
1
31
2
32
3
33
4
34
5
35
6
36
7
37
Shift
=
3D
' r
21
1 22
§
BF
$
24
%
25
&
26
/
2F
0
Graph
o
09
V\ AC
A AB
•X BA
8
EF
%u
BD
r
F4
/
ID
Shift
0 OA
2
FD
n
FC
:• F6
j
F5
\
IE
Code
s
EB
7C
@ 40
€
EE
C
87
e
9B
7
E7
\
5C
Shift
A
D8
, AD
Pt
9E
<r
BE
C
80
£
9C
r
E2
Normal
8
38
9
39
P El
dead
key
<
3C
u 81
■+
2B
d 94
Shift
(
28
)
29
*)
3F
>
3E
U
9A
*
2A
0 99
1
Graph
EC
•
07
!>
0D
60
(
AE
© 01
i.
Fl
4
06
1
Shift
B
08
fl
OE
*
27
1
AF
02
-+-
IF
♦
04
Code
[
5B
1 5D
8
E9
-
"3 >>
F3
0
ED
Cl)
DA
ii
B7
Shift
1 7B
1 7D
i.
A8
O V*
F2
4>
E8
Q
EA
0
B6
Normal
a
84
*
23
, 2C
. 2E
-
-
2D
a
61
b
62
Shift
A 8E
y\
5E
: 3A
.
.
5F
A
41
B
42
2
Graph
+
05
7E
y
FB
1 16
-
-
17
-
C4
- 1 - 11
Shift
V
03
—
BB
~
F7
=
=
F0
1
FE
Code
ij
B9
a
E5
a
86
a
A6
0
A7
a
E0
O
97
Shift
U
B8
E4
A
8F
Normal
c
63
d
64
e
65
f
66
R
67
h
68
i 69
j
6A
Shift
C
43
D
44
E
45
F
46
G
47
H
48
I
49
J
4A
3
Graph
0
BC
■" C7
▼
CD
h
14
+
15
-{
13
m
DC
| C6
Shift
-
FA
SCI
▲
CE
■
D4
-
10
m
D6
■
DF
|CA
Code
i 8D
I 8B
1
8C
/
9F
y
98
a B1
1
A1
ae
91
Shift
A
B0
JE
92
a
6B
E3
D
m
q
71
r
72
1
B
m
M
4D
N
4E
m
Q
51
R
52
ii
El
KB
D1
^CC
r
18
psiiii
mm
| C9
*
0C
B
D3
E
CB
r
A9
D
B3
B5
E6
n
A4
1
1
a
83
6
93
H
m
KB
El
K3l
m
■a
I
u
75
V
76
m
a
El
Shift
s
53
T
54
m
□
KP
5A
Y
59
B
IH
II
i
19
<5-
OF
El
§.ggi
L
F9
"l
m
EB
Code
e
89
0
96
6
82
d
95
6
88
<5
8A
a
A0
a
85
Shift
E
90
¥
9D
325
INTERNATIONAL MSX VERSIONS
o Layout French
326
INTERNATIONAL MSX VERSIONS
o Decode French
1
= R
0
1
2
3
4
5
6
7
a
85
&
26
e.
82
1 22
' 27
(
28
§
BF
e
8A
Normal
Shift
0
30
1
31
2
32
3
33
4
34
5
35
6
36
7
37
0
O 09
£
AC
34 AB
M BA
—
BB
7
EF
f
F'4
FB
Graph
Shift
Q 0A
! 16
2
ED
n
FC
F7
J
F5
Code
8
EB
7C
8 40
a
E0
60
1 7B
A
5E
€
EE
Shift
a
D8
i AD
E
90
pt
9E
r
5B
IT
BE
-
7E
Normal
' 21
C
87
)
29
-
2D
<
3C
*
$
24
m
6D
Shift
8
38
9
39
o
F8
_
5E
>
3E
*
2A
M
4D
Graph
CO
EC
♦
07
©
01
—
17
<
AE
fL
>
0D
4
06
1
Shift
B
08
02
-+- IF
>
AF
* ’ rt
Qj
fl
0E
♦
04
Code
7
E7
8
E9
I 7D
0
ED
<
F3
e 9B
U
R7
Shift
i
E2
c
80
]
5D
<1>
E8
F2
0
B6
Normal
a
97
ft
23
; 3B
: 3A
rr
3D
Q
71
b
62
Shift
% 25
£
9C
. 2E
/
2F
F
2B
Q
51
B
42
2
Graph
4
05
%o
BD
-r
F6
\
IE
£
FI
-
C4
_L
11
Shift
¥
03
/
ID
EE
F0
| FE
Code
ij
B9
a
E5
a
86
a
A6
o
A7
a 84
0 El
Shift
U
B8
X E4
A
8F
\
5C
A
8E
Normal
c
63
d
64
C
65
f
66
g
67
h
68
i 69
j
6A
Shift
c
43
D
44
E
45
F
46
G 47
H
48
I
49
J
4A
3
Graph
0
BC
^ C7
▼
CD
|- 14
15
13
m
DC^
1 C6
Shift
-
FA
h
Cl
▲
CE
■
D4
4
■
D6
m
DF
|CA
Code
i 8D
V 8B
l
8C
6
94
ii
81
a
B1
i A1
ae
91
Shift
O 99
u
9A
A
B0
JE
92
Normal
k
6B
1
6C
, 2C
n
6E
0
6F
P
70
a
61
r
72
Shift
K
4B
L
4C
7
3F
N
4E
0
4F
P
50
A
41
R
52
4
Graph
| DD
■
C8
0B
J
IB
■ C2
1
\\
\\
CC
18
Shift
| DE
1 |C9
■?
OC
■
D3
“ C3
5
X^CB
r
A9
Code
T
B3
0
B5
u
E6
n
A4
6
A2
Q
A3
a
83
a
93
Shift
T
B2
0
B4
i
A8
N
A5
n
E3
Normal
S
73
t
74
U
75
V
76
z
7A
X.
78
y
79
W
77
Shift
S 53
T
54
u
55
V
56
z
5A
X
58
Y
59
w
57
c
Graph
N D2
"T
12
CO
L 1A
► CF
X
1C
19
1*
OF
O
Shift
Xdi
t
D9
■
C5
■
D5
4 DO
•
F9
n
AA
Code
e
89
11
96
y
98
6
95
e
88
/
9F
a
A0
Cl)
DA
Shift
¥
9D
a
EA
327
INTERNATIONAL MSX VERSIONS
o Layout Japanese
328
INTERNATIONAL MSX VERSIONS
o Decode Japanese 1
J
1 S
o! i
2
3
4
5
6
7
Normal
0
30
1
31
2
32
3
33
4
34
'0
35
6
36
7
37
Shift
! 21
22
#
23
$
24
%
25
&
26
' 27
0
Graph
7j
OF
n
07
H
01
k
02
7K
03
X
04
<17
05
±
06
Kana
h
FC
4h(
E7
ec
*> 91
’)
93
94
4-J
95
A*
FI
Caps
V
DC
X
C7
CC
T
B1
B3
-r
B4
t
B5
Y
D4
Normal
8
38
9
39
2D
5E
¥
5C
40
c
5B
; 3B
_
Shift
(
28
) 29
3D
~
7E
, 7C
' 60
! 7B
1 2B
1
Graph
TX
0D
■ ; F
E0
—
17
l'J
09
o
84
4
82
Kana
F5
J:
F6
:.i ee
-'N.
ED
—
B0
-
DE
"
DF
ft
FA
Caps
-X
D5
y D6
IT
CE
CD
- BO
DE
•
DF
F
DA
Normal
: 3A
J 5D
, 2C
2E
_
2F
a
61
b
62
Shift
*
2 A
1 7D
<
3C
'>
3E
7 3F
—
5F
A
41
B
42
CM
Graph
81
•
85
>V
IF
k
ID
*
80
♦
83
J
IB
Kana
D 99
is
FI
^ nL
E8
h
F9
i O
F2
h
FB
G
El
-
9A
Caps
y
B9
D1
F
C8
D9
D2
n
DB
-f
Cl
17
BA
Normal
C
63
d
64
e
65
B
B
B
68
j
6A
Shift
c
43
D
44
E
45
F
46
G
47
II
48
B
J
4A
3
Graph
1 1A
U
14
-
18
+ 15
—1
13
0A
16
Kana
*
9F
1
9C
I''*
92
B
\
98
E6
i
EF
Caps
V
BF
BC
4
B2
^ CA
jf
B7
7
B8
—
C6
CF
Normal
k
613
1
6C
m
6D
n
6E
0
6F
P
70
q
71
r
72
Shift
K
4T3
I.
4C
M
ID
N
4E
0
4F
P
50
Q
51
R
52
4
Graph
+
IE
OB
7 7
10
i 12
Kana
<r>
E9
0
F8
i
F3
F0
7-5
F7
At
9E
k
E0
9D
Caps
/
C9
0
D8
-V-
D3
1
DO
7 D7
BE
7
CO
A
BD
Normal
s 73
t
74
U
75
v 76
w
77
X
78
y
79
z
7A
Shift
S 53
T
54
u
55
V 56
w
57
X
58
Y
59
z
5 A
5
Graph
OC
-
19
1 11
X
1C
¥
08
Kana
>
E4
96
£
E5
EB
-r 1
k.
E3
£
9B
FD
-o
E2
Caps
I- C4
t)
B6
i-
C5
CB
T
C3
BB
>
DD
•y
C2
329
INTERNATIONAL MSX VERSIONS
o Decode Japanese 2
INTERNATIONAL MSX VERSIONS
5.2.5 DEAD-KEY Functions
When an "a", "e", "i", "o", "u n , or "y" key is entered after the
SHIFT, GRAPHICS, CODE, or DEAD keys are entered, the accented
character is entered instead. The dead-key is valid only for
the "a", "e", "i", "o", "u", "y", and SPACE keys.
If a designated character does not exist in the character set, a
normal (non-accented) character is entered. For example, when
the dead key and a "Y" key of the international keyboard are
pressed, an accent grave "y" is not entered, and a normal "y" is
entered.
The dead-key is an optional provision. The dead-key is less
useful in the French and German versions, where special
keyboards must be used, and in English-speaking countries.
Application programs that must use this dead-key are less
compatible with other versions.
USA, UK, INT Versions
I Mode I Function
1 Normal
[Accent
grave
(') 1
1 Normal
shift 1 Accent
egu
(*) I
(Graph
1Accent
grave
(') 1
1—
1 Graph
shift
[Accent
egu
(•) i
ICode
[Accent
circonflex
r> i
r
ICode shift
1 “
1 Umlaut
( ) i
331
INTERNATIONAL MSX VERSIONS
DIN version
! Mode
j—_ _ _
----
1 Function
}
1 Normal
|—-.
(Accent grave
rV\
(Normal shift
|-
.(Accent egu
(') 1
iGraph
1 Accent grave
-(
D 1
*See Note 1.
1 Graph shift
(Accent egu
*See Note 1.
1 Code
lAccent circonflex
r> i
iCode shift
1Umlaut
(Ti
*Note I: In the DIN version, when the SHIFT, GRAPH, or
are pressed, an accent sign without a letter
French version
r— — ——t i
I Mode I function I
H-^
1 Normal
lAccent
circonflex
r> i
1 Normal shift 1 Umlaut
n;
IGraph
\ — _
lAccent
circonflex
C) t
IGraph shift
|-- -
1 Umlaut
( ) i
1 Code
lAccent
circonflex
r> i
ICode shift
1 Umlaut
TTi
4
DEAD keys
is entered.
332
INTERNATIONAL MSX VERSIONS
In the DIN and French versions, when the SPACE key is pressed
either the SHIFT, GRAPH, CODE, or DEAD keys are pressed, an
accent sign without alphabet is entered as follows.
r i-—->-—-,
I Mode I DIN I French I
i-1-1-1
(Normal lAccent grave (')lAccent circonflex I
*“ --H—-H-^
iNormal shiftlAccent egu {') I Space I
I h—-1-1
(Graph ((*See Note 1.) lAccent circonflex ( A )I
h — —— — — - - -- ______ ___________ ^
(Graph shift ( (*See Note 1.) iSpace I
I--h-H-1
(Code lAccent circonflex (^) lAccent circonflex (*) I
I-H-H-—-H
ICodeshift ISpace ISpace I
5.3 Screen Mode
The vertical synchronize frequencies and the default screen
modes of the different versions are as follows.
I I iDefaultiDefaultlDefault screen width
I Version IV. Sync. I screen Iborder - --i-
I I I mode I col or I SCREEN 0 I SCREEN 1
I Japan I
L- H
IDSA I
V -+-
IUK I
h - H
I DIN I
f--^
I French I
l--+
IINT I
I 1 I 7 I
6 0Hz h-H-H
I I I
50 Hz
39
37
333
INTERNATIONAL MSX VERSIONS
5.4 Other Differences among Versions
The default function for the F6 key differs as follows.
r ---r~ —— —--—--j
I Japanese I color 15,4,7 1
i-——i-1
lOthers Icolor 15,4,41
The Japanese version has a Hiragana-to-Katakana converter for
non-MSX printers; however, other versions do not have this
feature.
The format symbols for the PRINT USING statement that differ
among international versions are as follows.
I Purpose (Japanese I UK I Others I
t™ ————_ —— -~-1-1 -— — — H -1
I Currency sign I Yen ¥ I Pound £ I $ I
i — —-—-1--I-1-1
I Fixed-length string field I & I \ I
i — i-+-t
IVariable-length string fieldl @1 & I
The VDP interrupt interval is equal to the vertical synchronize
frequency, or 1/60 second in the Japanese and USA versions, and
1/50 second in other versions. This has an effect on the
interval to increment the TIME variable.
The symbol for integer division is the Yen sign in the Japanese
version and in all other versions.
The format of DATE used for MSX-DOS is 'yy-mm-dd' (Year, Month,
Date) in Japanese version, 'mm-dd-yy 1 in USA version and 'dd-mm-
yy' in European versions.
334
INTERNATIONAL MSX VERSIONS
5.5 ID Bytes
You can build software having compatibility with all MSX
versions by using the following information supplied in the
system ROM.
The format of the ID bytes are as follows:
2BH: B7 B6 B5 B4 B3 B2 B1 BO
1 I I I I I I I
I I I I <—x— j—T ype of character generator
j!l! 0: Japanese 1: International
I'll 2: Korean
1111
| i— j.— j-Date format
[ 0: Y-K-D 1: M-D-Y 2: D-M-Y
' Interrupt frequency
0: 60Hz Is 50Hz
2CH: B7 B6 B5 B4 B3 B2 B1 BO
I I I I I I I I
| | | | i—j— j—T ype of keyboard
j I I I 0: Japanese 1: International
i I I I 2: French 3: UK 4: DIN
L — JJ — J -Version of BASIC
0: Japanese 1: International
335
NOTES FOR MSX SOFTWARE DEVELOPERS
6. Notes for MSX Software Developers
1) Do not write programs to directly handle the hardware. Use
routines prepared in BIOS so as to isolate the software from
the hardware and make future changes to the hardware without
affecting the existing software possible. The BIOS is built to
access its functions via a jump table beginning at address 0000.
The jump table contains jump vectors functions that handle the
hardware of the MSX computer. By using the functions provided
by BIOS, application programs can access the MSX hardware
without modification, even though the hardware is different.
Fot example, the current MSX scans the keyboard by using 8255
PPI. In the near future, however, there may be computers
having separate keyboards using an infrared communication link.
This new computer may not use the 8255 PPI; it might use some
other chip to do serial communications to handle the keyboard.
If the software scanning the keyboard uses the 8255 directly,
the new computer would not support the software.
The only exception to the above rule is the VDP. To allow fast
data transfer with the VDP, the ROM contains the locatios of
the VDP in addresses 0006 and 0007. Address 0006 contains the
read address of the VDP and address 0007 contains the write
address to the VDP. If the software needs to transfer data at
a high speed, the program can access the VDP directly using
these addresses contained in ROM with the indirect addressing
mode.
In addition, address 0004 contains the address of the character
pattern generator table stored in ROM. This may be of use to
some programs that must keep track of the location of the table.
2) Do not use RAM locations above F380H if you do not have
detailed documentation on the meanings of these locaations.
This area is used by the system for working storage and access
to these locations may cause your program to malfunction or to
be incompatible with versions released in the future. All
locations that are unused in the current MSX version within the
above area are reseved for future expansion.
336
NOTES FOR MSX SOFTWARE DEVELOPERS
3) Software that has to interact with other programs must be
designed in a way that it does not alter the programming
environment. Major considerations are as follows.
o Allocate work space
o Share HOOKs
4) There are differences among versions of MSX sold in different
countries. These differences have been restricted to the
keyboard layout and the character generators. The locations
2BH and 2CH contain the special ID bytes that indicate the
characteristics of the ROM. Software should be written to refer
to these locations so as to work on any international version.
See section 5.5 ’ID bytes’ for details.
5) Programs distributed in ROM cartridges must run in any slot/
primary or secondary. Some of the game software that have been
developped can run only in slot 1, or only in non-expanded slot.
This DOES cause a big problem.
Programs which use the MSX-BASIC interpreter with system CALL
statements or device expansion mechanisms, must also determine
the number of the slot in which the cartridge is inserted.
Programs which run independently from the MSX-BASIC interpreter
(such as game programs) do not have to determine the location
of the cartridge unless they use the CALSLT routine, the CALBAS
routine, or the 1 RST 30H'; or if the program occupies more than
one page (for example the first 16K in 4000H..7FFFH, or the
second 16K in 8000H....OBFFFH). This is because slot exchanges
are not done during program execution. For example, if you
want to call a routine in your program from an interrupt hook,
simply do a 'JP' instruction, not 'RST 30H’, because your
routine will always be there.
337
NOTES FOR MSX SOFTWARE DEVELOPERS
|
Use the following routine to know where you are: ;
; This routine returns the slot address in the following format
i in [Acc].
FxxxSSPP
I Mil
I I I — Primary slot # (0-3)
I tJ -Secondary slot # (0-3)
1 -1 if secondary slot # specified
This value can later be used as an input parameter for the
RDSLT, WRSLT, CALSLT, ENASLT and ' RST 3 OH'.
RSLREG
EQU
138H
EXPTBL
EQU
0FCC1H
B8000
EQU
0
;Set this to non-zero if the program
; resides at 8000..0BFFFH
WHERE_AH_I:
CALL
RRC
RRC
RSLREG
;Read primary slot #
;Move it to bit 0,1 of [Acc]
IF
B8000
RRC
RRC
ENDIF
ANI
11B
MOV
C, A
MVI
B,0
LXI
H,EXPTBL
;See if this slot is expanded or not
DAD
B
ORA
M
;Set MSB if so
RP
;Not expanded, all done
MOV
C, A
;Save primary slot number
INX
H
jPoint to SLTTBL entry
INX
H
INX
H
INX
H
IF
MOV
B8000
A, M
;Get what is currently output to
; expansion slot register
RRC
;Move it to bit 2,3 of [Acc]
RRC
ENDIF
ANI
1100B
ORA
C
;Finally form slot address
RET
338
NOTES FOR MSX SOFTWARE DEVELOPERS
• m • •
If your program occupies 32K from 4000H..OBFFFH, and
the execution begins from the INIT entry of the ROM
at 4000H..7FFFH, use the following routine to enable the
last half:
trtritttftttffirsrititittr
trttttfti
9 9 9 9 9 9
ENASLT EQU
24H
CALL
WHERE_AM_I
MV I
H, 80H
CALL
ENASLT
6) When changing the contents of register 0 or 1 of the VDP to
change the display modes, do not write immediate values to them.
Their current contents are always stored in RGOSAV and RG1SAV,
respectively, so get their contents first, then mask off the
unnecessary bits and add your own bits by using AND and OR
instructions. Leave the other bits unchanged. This is necessary
because some manufacturers use the EV (External Video) bits to
allow superimposing.
7) When writing values to the various base address registers of
the VDP, always write 0's to the unused bits near the MSB. This
is important because it makes it possible to expand the
capabilities of the VDP while maintaining compatibility with
the current 9918-compatible VDP.
8) BIOS provides two ways to read the keyboard. Use the routines
depending ori to your needs.
1. Physical key position and real-time keyboard status as
returned value needed.
Use SNSMAT entry
2. Logical character code needed as a returned value.
Use CHSNS and CHGET
339
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